The document summarizes various types of storage systems used with personal computers. It describes the characteristics of hard drives and discusses magnetic hard drives and solid state drives. It covers optical discs like CDs, DVDs, and Blu-ray discs as well as their read-only, recordable, and rewritable varieties. Flash memory storage devices such as USB flash drives and memory cards are also outlined. The document briefly mentions other storage systems including network storage, smart cards, holographic storage, and large computer storage systems.
The document discusses different types of computer storage systems. It describes hard drives, optical discs like CDs and DVDs, and flash memory storage. Hard drives use magnetic disks and can be internal or external. Optical discs use lasers to read and write data in pits and lands. Flash memory has no moving parts and is used in devices like memory cards and USB drives. Other storage discussed includes remote storage in the cloud, magnetic tape backups, and RAID arrays for large systems. The document provides an overview of common storage characteristics and alternatives for personal computers.
The process of storing personal data or information for future use is called storage of data. Storage involves writing data to storage devices and reading it back from storage devices later. Common storage devices include hard disks, flash drives, optical discs, cloud storage, and tape drives. The amount of data a storage device can hold is called its storage capacity, which is typically measured in bytes, kilobytes, megabytes, or terabytes.
The document discusses various types of computer storage and memory. It describes primary storage such as RAM and cache memory that is directly accessible by the CPU. Secondary storage like hard drives and SSDs are non-volatile but not directly accessible. Tertiary storage provides very large scale storage through tape libraries and optical jukeboxes. Other storage types discussed include offline storage, network storage, flash memory, magnetic tape, solid state drives, hard drives, optical discs like CDs and Blu-rays, as well as various memory technologies.
The document discusses various types of storage media including hard drives, floppy disks, tape, Zip disks, CDs, DVDs, Blu-ray discs, USB flash drives, memory cards, solid state drives, and cloud storage. It provides details on the capabilities and uses of each medium. Hard drives can permanently store large amounts of data but are not portable, while removable media like floppy disks, Zip disks, CDs, DVDs, and USB flash drives allow portability but have more limited storage capacity. Newer technologies like solid state drives and cloud storage provide higher speeds and capacity.
The document discusses various storage media including hard drives, floppy disks, tape, Zip disks, CDs, DVDs, Blu-ray discs, USB flash drives, memory cards, and solid state drives. It provides details on the capabilities, uses, advantages and limitations of each type of storage medium. The key points are that storage media are any devices or materials used to store data, and range from internal hard drives to removable options like disks, cards, and drives that allow transferring and sharing data between computers or other devices.
Hard disk drives (HDDs) are data storage devices that store and retrieve digital information using rapidly rotating disks coated with magnetic material. HDDs have greatly increased in capacity over time, from megabytes to terabytes, while decreasing dramatically in size and cost. Key components include disks, read/write heads, and an actuator arm that moves the heads over the disks. Error correction allows high recording densities without data loss. Future developments may allow even higher capacities through new magnetic recording technologies.
The document provides information about secondary storage. It begins by defining secondary storage as non-volatile, long-term storage used to store programs and data when a computer is switched off. The main types of secondary storage are magnetic storage devices like hard disk drives. Advantages of secondary storage include safety, reliability, permanence, and ability to store huge volumes of data cheaply. Disadvantages are slower speed compared to primary storage. Common secondary storage devices discussed include hard disks, optical discs like CDs and DVDs, USB flash drives, memory cards, and smart cards.
The document discusses different types of computer storage systems. It describes hard drives, optical discs like CDs and DVDs, and flash memory storage. Hard drives use magnetic disks and can be internal or external. Optical discs use lasers to read and write data in pits and lands. Flash memory has no moving parts and is used in devices like memory cards and USB drives. Other storage discussed includes remote storage in the cloud, magnetic tape backups, and RAID arrays for large systems. The document provides an overview of common storage characteristics and alternatives for personal computers.
The process of storing personal data or information for future use is called storage of data. Storage involves writing data to storage devices and reading it back from storage devices later. Common storage devices include hard disks, flash drives, optical discs, cloud storage, and tape drives. The amount of data a storage device can hold is called its storage capacity, which is typically measured in bytes, kilobytes, megabytes, or terabytes.
The document discusses various types of computer storage and memory. It describes primary storage such as RAM and cache memory that is directly accessible by the CPU. Secondary storage like hard drives and SSDs are non-volatile but not directly accessible. Tertiary storage provides very large scale storage through tape libraries and optical jukeboxes. Other storage types discussed include offline storage, network storage, flash memory, magnetic tape, solid state drives, hard drives, optical discs like CDs and Blu-rays, as well as various memory technologies.
The document discusses various types of storage media including hard drives, floppy disks, tape, Zip disks, CDs, DVDs, Blu-ray discs, USB flash drives, memory cards, solid state drives, and cloud storage. It provides details on the capabilities and uses of each medium. Hard drives can permanently store large amounts of data but are not portable, while removable media like floppy disks, Zip disks, CDs, DVDs, and USB flash drives allow portability but have more limited storage capacity. Newer technologies like solid state drives and cloud storage provide higher speeds and capacity.
The document discusses various storage media including hard drives, floppy disks, tape, Zip disks, CDs, DVDs, Blu-ray discs, USB flash drives, memory cards, and solid state drives. It provides details on the capabilities, uses, advantages and limitations of each type of storage medium. The key points are that storage media are any devices or materials used to store data, and range from internal hard drives to removable options like disks, cards, and drives that allow transferring and sharing data between computers or other devices.
Hard disk drives (HDDs) are data storage devices that store and retrieve digital information using rapidly rotating disks coated with magnetic material. HDDs have greatly increased in capacity over time, from megabytes to terabytes, while decreasing dramatically in size and cost. Key components include disks, read/write heads, and an actuator arm that moves the heads over the disks. Error correction allows high recording densities without data loss. Future developments may allow even higher capacities through new magnetic recording technologies.
The document provides information about secondary storage. It begins by defining secondary storage as non-volatile, long-term storage used to store programs and data when a computer is switched off. The main types of secondary storage are magnetic storage devices like hard disk drives. Advantages of secondary storage include safety, reliability, permanence, and ability to store huge volumes of data cheaply. Disadvantages are slower speed compared to primary storage. Common secondary storage devices discussed include hard disks, optical discs like CDs and DVDs, USB flash drives, memory cards, and smart cards.
Secondary storage devices such as hard disks, CDs, USB drives, and Blu-ray discs are used for bulk storage of data with large capacities and transfer data to main memory for processing. Hard disks provide fast storage and high capacities, storing data on magnetic disks accessed by read/write heads. CDs and Blu-ray discs use optical technology to store digital data in pits encoded in spiral tracks, with Blu-ray using a blue laser to achieve higher densities. USB drives are portable flash memory devices that can easily transfer data between computers. Secondary storage is cheaper than main memory and has slower access times.
Fixed hard disks are used for storing operating systems and applications on a computer. They have high access speeds and storage capacities but cannot be removed from the computer. Portable hard disks can store large files and transfer them between computers, but can be easily stolen. Magnetic tapes provide extremely large storage capacities for backups but have slow access speeds. Optical disks like CDs and DVDs are used to distribute software, movies and files but have slower data rates than hard disks. Solid state storage like memory sticks are small, robust and portable but have lower capacity and speeds than hard disks. Backups protect against data loss by making copies of files and storing them separately from the originals.
Optical storage uses light to read data stored on optical discs or memory cards. Common optical storage devices include CDs, DVDs, Blu-Ray discs, HD DVDs, USB flash drives, memory cards, and smart cards. CDs hold around 800MB of read-only data, while DVDs and Blu-Ray discs can hold significantly more data up to 50GB in writable formats, using laser light of different wavelengths to read small pits in the disc's surface. Flash memory cards and drives store data electronically in non-volatile memory.
The document discusses the history and technology of hard disk drives (HDDs). It describes how HDDs store data using rapidly rotating magnetic disks and read/write heads. Key points covered include:
- HDDs were introduced in 1956 and have since increased enormously in capacity while decreasing dramatically in size, weight, and cost.
- HDDs use magnetic recording to store data as magnetic patterns on disks, with read/write heads detecting and modifying magnetism on spinning disks.
- Components include spinning disks, read/write heads on an arm, and motors to spin disks and position heads. Error correction allows higher storage densities.
Hard disk & Optical disk (college group project)Vshal_Rai
- Hard disk drives (HDDs) are devices used for digital data storage. They consist of rapidly rotating discs coated with magnetic material. Magnetic heads write data to and read data from the disc surfaces.
- HDDs were first introduced in 1956 and have since decreased dramatically in size and cost, becoming standard in personal computers by the late 1980s. Capacities have also increased greatly, with modern HDDs capable of storing terabytes of data.
- Optical discs like CDs and DVDs store data in the form of pits and lands on a reflective surface. They were invented in the late 1950s and early 1960s and are now commonly used to store music, video, and computer programs and data.
This presentation provides an overview of different storage devices, including their basic units of data storage (bits, bytes, kilobytes, etc.), data access methods (random access vs sequential access), and specific device types. It discusses magnetic disks like hard disks, floppy disks, and zip disks. It also covers optical disks such as CDs, DVDs, and Blu-Ray disks. Finally, it examines flash memory storage options including solid state drives, USB flash drives, memory cards, and more.
Storage devices
This lesson includes the following sections:
Categorizing Storage Devices
Magnetic Storage Devices
Optical Storage Devices
Storage devices hold data, even when the computer is turned off.
The physical material that actually holds data is called a storage medium. The surface of a floppy disk is a storage medium.
The hardware that writes data to or reads data from a storage medium is called a storage device. A floppy disk drive is a storage device.
The two primary storage technologies are magnetic and optical.
Diskettes (floppy disks)
Hard disks
High-capacity floppy disks
Disk cartridges
Magnetic tape
Compact Disk Read-Only Memory (CD-ROM) A magnetic disk's medium contains iron particles, which can be polarized—given a magnetic charge—in one of two directions.
Each particle's direction represents a 1 (on) or 0 (off), representing each bit of data that the CPU can recognize.
A disk drive uses read/write heads containing electromagnets to create magnetic charges on the medium.
Digital Video Disk Read-Only Memory
(DVD-ROM)
CD-Recordable (CD-R)
CD-Rewritable (CD-RW)
PhotoCD
Optical storage media such as CDs and DVDs are used to store large files like music, videos, and software. CDs hold up to 1GB of data while DVDs can store several GB. Both are portable. CD-ROMs/DVD-ROMs are used to prevent deletion of data by software, music, and publishing companies. CD-Rs/DVD-Rs are for single burn recordings of music, videos, or backups. CD-RWs/DVD-RWs allow updating files. DVD-RAM is housed in a cartridge for video recording and computer memory. Blu-ray has the largest storage capacity of optical media. Solid state storage is small, robust, and expensive removable
Hard disks are part of disk drives that store and provide quick access to large amounts of data on electromagnetically charged surfaces. They have large storage capacities, use metallic platters for storage, and are faster than floppy disks or CD-ROMs. Hard disks store programs, operating systems, and personal files, retaining data even when the computer is off. There are three types: digital versatile discs, external hard disks, and internal hard disks. However, hard disks can eventually fail and stop the computer from working, and head crashes can damage disks and cause data loss.
This document summarizes different types of storage devices and media, including their basic functions and uses. It discusses magnetic devices like floppy disks, hard drives, and tape; optical media like CDs, DVDs, and Blu-ray discs; and solid state drives like USB flash drives, memory cards, and SSDs. For each type, it provides details on how they work, common applications, and advantages and disadvantages compared to other options. The document aims to explain the key characteristics and purposes of various storage technologies.
The document defines optical storage and discusses optical disc drives. It explains that optical drives use lasers to read and write data to optical discs by detecting light reflections from bumps and areas on the disc's surface. The document outlines different types of optical media like CDs, DVDs, and Blu-rays, as well as read-only, rewritable, double-sided, and double-layer media. It also describes how optical drives spin and move discs to read data and how recorders encode data onto discs using lasers.
The document discusses various types of secondary storage devices. It describes floppy disks, hard disks, optical disks, solid-state storage, internet drives, magnetic tape, and mass storage devices. It explains the characteristics and capabilities of each type of storage including capacity, access speed, portability and applications used. The document also discusses technologies for improving hard disk performance and emerging technologies that could store an entire life's data on a single disk in the future.
Hard disks and optical disks are both used for data storage. Hard disks use spinning magnetic platters and read/write heads to store data non-volatilely even without power. Optical disks like CDs, DVDs, and Blu-Rays use lasers and reflective layers to store data in the form of pits and lands on polycarbonate disks. Optical disks allow for higher density storage than early hard disks and are portable, but have slower access speeds and more complex drive mechanisms.
This document discusses the components and operation of hard disk drives. It describes how hard disks store data using longitudinal or perpendicular magnetic recording. The key components of a hard disk drive are platters, read/write heads, cylinders, and a spindle. Platters are coated disks that store data magnetically. Read/write heads barely touch the platter surface to read and write data. Cylinders refer to vertical sections of tracks that pass through all platters. The spindle holds the platters and rotates them at high speeds during operation.
Storage holds data and information for future use. Common storage media include hard disks, SSDs, flash drives, and optical discs. Storage capacity is measured in bytes, kilobytes, megabytes, and larger units. A storage device contains hardware that writes data to storage media and reads data from storage media. Common interfaces that connect hard disks include PATA, SATA, SCSI, and SAS. Hard disks contain spinning platters, read/write heads, and motors, while SSDs use flash memory. RAID configurations like 0, 1, 5, and 1+0 provide different balances of performance and redundancy.
Cloud storage allows users to store files on remote servers accessed via the internet. It offers benefits like accessing files from any device with internet, sharing files easily, offsite backups, and relieving enterprises of data storage tasks. Optical disks like CDs and DVDs store data locally as microscopic pits and lands read by lasers. Common optical disk formats include CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-R, DVD-RW and Blu-ray disks, which have higher storage capacities than DVDs. Optical disks allow both read-only and rewritable options while cloud storage depends on subscription plans that may charge monthly fees.
Secondary storage devices are not directly accessible by the CPU and do not lose data when powered down. Common secondary storage devices include magnetic tapes for storing large amounts of data cheaply, hard disks for quick access to large amounts of gigabytes of storage, floppy disks for smaller storage and transport of documents between computers, and optical disks like CDs and DVDs which use lasers to store and access digital data for music, video, programs and more. DVDs specifically store over six times more data than CDs using the same physical dimensions through optical disc storage technology developed in 1995.
The document discusses various storage technologies used in computing. It describes the two primary storage types as magnetic and optical. Magnetic storage includes hard disks, diskettes, magnetic tape, and solid-state drives. Optical storage includes CDs, DVDs, and Blu-ray discs. Other technologies discussed include smart cards, USB flash drives, and RFID tags.
The document provides an introduction to hard disk drives including their main components and how they work. It discusses the geometry of hard drives including heads, cylinders, and sectors per track. It describes the parts of a hard drive like platters, arms, and motors. It covers characteristics of hard drives like seek time and interfaces. It explains what a hard disk partition is and reasons for creating multiple partitions like using different file systems or operating systems.
Este documento resume las normas de citación y referencias bibliográficas del estilo APA (American Psychological Association). Explica que el formato APA se utiliza convencionalmente en ciencias sociales y que los textos deben estar en doble espacio. Detalla los tres niveles de títulos y cómo citar cuando hay uno o varios autores. También cubre citas textuales, el orden alfabético de referencias y ejemplos de referencias para revistas, libros y medios electrónicos.
Viet Delta Company is located in Ho Chi Minh City, Vietnam. They have issued a beneficiary's certificate to Yoko Food and Agro Ltd. in Dhaka, Bangladesh. The certificate confirms that Viet Delta Company will send a full set of non-negotiable documents to Yoko Food within 7 days of shipping 2,000 kilograms of goods. The shipment has a gross weight of 2,040 kilograms and is associated with Letter of Credit number 175112010110 dated March 27, 2012.
Secondary storage devices such as hard disks, CDs, USB drives, and Blu-ray discs are used for bulk storage of data with large capacities and transfer data to main memory for processing. Hard disks provide fast storage and high capacities, storing data on magnetic disks accessed by read/write heads. CDs and Blu-ray discs use optical technology to store digital data in pits encoded in spiral tracks, with Blu-ray using a blue laser to achieve higher densities. USB drives are portable flash memory devices that can easily transfer data between computers. Secondary storage is cheaper than main memory and has slower access times.
Fixed hard disks are used for storing operating systems and applications on a computer. They have high access speeds and storage capacities but cannot be removed from the computer. Portable hard disks can store large files and transfer them between computers, but can be easily stolen. Magnetic tapes provide extremely large storage capacities for backups but have slow access speeds. Optical disks like CDs and DVDs are used to distribute software, movies and files but have slower data rates than hard disks. Solid state storage like memory sticks are small, robust and portable but have lower capacity and speeds than hard disks. Backups protect against data loss by making copies of files and storing them separately from the originals.
Optical storage uses light to read data stored on optical discs or memory cards. Common optical storage devices include CDs, DVDs, Blu-Ray discs, HD DVDs, USB flash drives, memory cards, and smart cards. CDs hold around 800MB of read-only data, while DVDs and Blu-Ray discs can hold significantly more data up to 50GB in writable formats, using laser light of different wavelengths to read small pits in the disc's surface. Flash memory cards and drives store data electronically in non-volatile memory.
The document discusses the history and technology of hard disk drives (HDDs). It describes how HDDs store data using rapidly rotating magnetic disks and read/write heads. Key points covered include:
- HDDs were introduced in 1956 and have since increased enormously in capacity while decreasing dramatically in size, weight, and cost.
- HDDs use magnetic recording to store data as magnetic patterns on disks, with read/write heads detecting and modifying magnetism on spinning disks.
- Components include spinning disks, read/write heads on an arm, and motors to spin disks and position heads. Error correction allows higher storage densities.
Hard disk & Optical disk (college group project)Vshal_Rai
- Hard disk drives (HDDs) are devices used for digital data storage. They consist of rapidly rotating discs coated with magnetic material. Magnetic heads write data to and read data from the disc surfaces.
- HDDs were first introduced in 1956 and have since decreased dramatically in size and cost, becoming standard in personal computers by the late 1980s. Capacities have also increased greatly, with modern HDDs capable of storing terabytes of data.
- Optical discs like CDs and DVDs store data in the form of pits and lands on a reflective surface. They were invented in the late 1950s and early 1960s and are now commonly used to store music, video, and computer programs and data.
This presentation provides an overview of different storage devices, including their basic units of data storage (bits, bytes, kilobytes, etc.), data access methods (random access vs sequential access), and specific device types. It discusses magnetic disks like hard disks, floppy disks, and zip disks. It also covers optical disks such as CDs, DVDs, and Blu-Ray disks. Finally, it examines flash memory storage options including solid state drives, USB flash drives, memory cards, and more.
Storage devices
This lesson includes the following sections:
Categorizing Storage Devices
Magnetic Storage Devices
Optical Storage Devices
Storage devices hold data, even when the computer is turned off.
The physical material that actually holds data is called a storage medium. The surface of a floppy disk is a storage medium.
The hardware that writes data to or reads data from a storage medium is called a storage device. A floppy disk drive is a storage device.
The two primary storage technologies are magnetic and optical.
Diskettes (floppy disks)
Hard disks
High-capacity floppy disks
Disk cartridges
Magnetic tape
Compact Disk Read-Only Memory (CD-ROM) A magnetic disk's medium contains iron particles, which can be polarized—given a magnetic charge—in one of two directions.
Each particle's direction represents a 1 (on) or 0 (off), representing each bit of data that the CPU can recognize.
A disk drive uses read/write heads containing electromagnets to create magnetic charges on the medium.
Digital Video Disk Read-Only Memory
(DVD-ROM)
CD-Recordable (CD-R)
CD-Rewritable (CD-RW)
PhotoCD
Optical storage media such as CDs and DVDs are used to store large files like music, videos, and software. CDs hold up to 1GB of data while DVDs can store several GB. Both are portable. CD-ROMs/DVD-ROMs are used to prevent deletion of data by software, music, and publishing companies. CD-Rs/DVD-Rs are for single burn recordings of music, videos, or backups. CD-RWs/DVD-RWs allow updating files. DVD-RAM is housed in a cartridge for video recording and computer memory. Blu-ray has the largest storage capacity of optical media. Solid state storage is small, robust, and expensive removable
Hard disks are part of disk drives that store and provide quick access to large amounts of data on electromagnetically charged surfaces. They have large storage capacities, use metallic platters for storage, and are faster than floppy disks or CD-ROMs. Hard disks store programs, operating systems, and personal files, retaining data even when the computer is off. There are three types: digital versatile discs, external hard disks, and internal hard disks. However, hard disks can eventually fail and stop the computer from working, and head crashes can damage disks and cause data loss.
This document summarizes different types of storage devices and media, including their basic functions and uses. It discusses magnetic devices like floppy disks, hard drives, and tape; optical media like CDs, DVDs, and Blu-ray discs; and solid state drives like USB flash drives, memory cards, and SSDs. For each type, it provides details on how they work, common applications, and advantages and disadvantages compared to other options. The document aims to explain the key characteristics and purposes of various storage technologies.
The document defines optical storage and discusses optical disc drives. It explains that optical drives use lasers to read and write data to optical discs by detecting light reflections from bumps and areas on the disc's surface. The document outlines different types of optical media like CDs, DVDs, and Blu-rays, as well as read-only, rewritable, double-sided, and double-layer media. It also describes how optical drives spin and move discs to read data and how recorders encode data onto discs using lasers.
The document discusses various types of secondary storage devices. It describes floppy disks, hard disks, optical disks, solid-state storage, internet drives, magnetic tape, and mass storage devices. It explains the characteristics and capabilities of each type of storage including capacity, access speed, portability and applications used. The document also discusses technologies for improving hard disk performance and emerging technologies that could store an entire life's data on a single disk in the future.
Hard disks and optical disks are both used for data storage. Hard disks use spinning magnetic platters and read/write heads to store data non-volatilely even without power. Optical disks like CDs, DVDs, and Blu-Rays use lasers and reflective layers to store data in the form of pits and lands on polycarbonate disks. Optical disks allow for higher density storage than early hard disks and are portable, but have slower access speeds and more complex drive mechanisms.
This document discusses the components and operation of hard disk drives. It describes how hard disks store data using longitudinal or perpendicular magnetic recording. The key components of a hard disk drive are platters, read/write heads, cylinders, and a spindle. Platters are coated disks that store data magnetically. Read/write heads barely touch the platter surface to read and write data. Cylinders refer to vertical sections of tracks that pass through all platters. The spindle holds the platters and rotates them at high speeds during operation.
Storage holds data and information for future use. Common storage media include hard disks, SSDs, flash drives, and optical discs. Storage capacity is measured in bytes, kilobytes, megabytes, and larger units. A storage device contains hardware that writes data to storage media and reads data from storage media. Common interfaces that connect hard disks include PATA, SATA, SCSI, and SAS. Hard disks contain spinning platters, read/write heads, and motors, while SSDs use flash memory. RAID configurations like 0, 1, 5, and 1+0 provide different balances of performance and redundancy.
Cloud storage allows users to store files on remote servers accessed via the internet. It offers benefits like accessing files from any device with internet, sharing files easily, offsite backups, and relieving enterprises of data storage tasks. Optical disks like CDs and DVDs store data locally as microscopic pits and lands read by lasers. Common optical disk formats include CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-R, DVD-RW and Blu-ray disks, which have higher storage capacities than DVDs. Optical disks allow both read-only and rewritable options while cloud storage depends on subscription plans that may charge monthly fees.
Secondary storage devices are not directly accessible by the CPU and do not lose data when powered down. Common secondary storage devices include magnetic tapes for storing large amounts of data cheaply, hard disks for quick access to large amounts of gigabytes of storage, floppy disks for smaller storage and transport of documents between computers, and optical disks like CDs and DVDs which use lasers to store and access digital data for music, video, programs and more. DVDs specifically store over six times more data than CDs using the same physical dimensions through optical disc storage technology developed in 1995.
The document discusses various storage technologies used in computing. It describes the two primary storage types as magnetic and optical. Magnetic storage includes hard disks, diskettes, magnetic tape, and solid-state drives. Optical storage includes CDs, DVDs, and Blu-ray discs. Other technologies discussed include smart cards, USB flash drives, and RFID tags.
The document provides an introduction to hard disk drives including their main components and how they work. It discusses the geometry of hard drives including heads, cylinders, and sectors per track. It describes the parts of a hard drive like platters, arms, and motors. It covers characteristics of hard drives like seek time and interfaces. It explains what a hard disk partition is and reasons for creating multiple partitions like using different file systems or operating systems.
Este documento resume las normas de citación y referencias bibliográficas del estilo APA (American Psychological Association). Explica que el formato APA se utiliza convencionalmente en ciencias sociales y que los textos deben estar en doble espacio. Detalla los tres niveles de títulos y cómo citar cuando hay uno o varios autores. También cubre citas textuales, el orden alfabético de referencias y ejemplos de referencias para revistas, libros y medios electrónicos.
Viet Delta Company is located in Ho Chi Minh City, Vietnam. They have issued a beneficiary's certificate to Yoko Food and Agro Ltd. in Dhaka, Bangladesh. The certificate confirms that Viet Delta Company will send a full set of non-negotiable documents to Yoko Food within 7 days of shipping 2,000 kilograms of goods. The shipment has a gross weight of 2,040 kilograms and is associated with Letter of Credit number 175112010110 dated March 27, 2012.
Google Cloud SQL is a fully-managed MySQL database service hosted on Google's infrastructure that allows users to create, configure and manage cloud-based SQL databases without having to worry about maintenance, backups or other database administration tasks. It offers high availability, integration with other Google services, and pricing plans starting at $1 per day for small databases. Cloud SQL provides a familiar MySQL interface to help easily move applications and data into the cloud.
OBSERVATORIO CULTURAL DE PORTO ALEGRE Antecedentes y primeros pasosAlvaro Santi
Este ensayo tiene como propósito dar cuenta de los primeros pasos del Observatorio Cultural de la Secretaría Municipal de Cultura de Porto Alegre, y de los sucesos que los antecedieron
Could the five emerging markets of Brazil, India, Indonesia, South Africa and Turkey see their currency exchange rates plummet in 2014? John Hardy, of Saxo Bank, predicts they could if their current account deficits continue to expand. In this infographic, produced by Saxo Capital Markets, the major currencies are shown with their current account rates (as a percentage of GDP) plotted against their current exchange rate percentage change (from Jan 2013 to Oct 2013). Brazil, India, Indonesia, South Africa and Turkey are all seen to be falling behind, with their percentage rates firmly below zero.
The article is a report about testing of portability of Loki library with 64-...PVS-Studio
The document summarizes potential errors that can occur when developing 64-bit applications. It provides examples of code that works correctly in debug mode but fails or produces errors in release mode due to compiler optimizations hiding issues. The author recommends using static analysis tools like Viva64 to thoroughly check for these "phantom" errors, as even small code changes can expose failures. Testing only in debug and release modes may miss errors, so full static analysis is suggested to catch problems when porting code to 64-bit.
Ms. Fountain has over 30 years of experience in business, compliance, and auditing. She will give a presentation on maintaining objectivity and independence as a compliance professional. The presentation will discuss how to ensure independence in the compliance role, techniques for employing objectivity, and what to do when management challenges objectivity. It is aimed at compliance officers, risk officers, legal officers, auditors and other professionals to help prepare them for difficult situations regarding objectivity.
Este documento describe tres tipos de contenedores para desechos: uno para envases ligeros de plástico, latas y cartón; otro para envases de vidrio; y un último para residuos biodegradables y otros materiales como pilas, aceites y aerosoles.
Objectives
- Name several general properties of storage systems.
- Describe the two most common types of hard drives and what they are used for today.
- Discuss the various types of optical discs available and how they differ from each other.
- Identify some flash-memory-based storage devices and media and explain how they are used today.
- List at least three other types of storage systems.
- Summarize the storage alternatives for a typical personal computer.
Applicatiins of information and communicationTayyabSaif4
This is about applications of information and communication technologies where i discuss about operating system of software as well as application software and i brief them very good
This document discusses different types of storage devices, categorizing them as magnetic or optical. Magnetic storage devices include floppy disks, hard disks, and magnetic tape. Optical storage devices include CD-ROM, DVD-ROM, CD-R, and CD-RW. The document explains how data is stored on magnetic disks using polarized particles and on optical disks using pits and lands that reflect light differently. It provides details on formatting disks and the areas created, capacities of different devices, and speeds of CD-ROM and DVD drives.
This chapter discusses different types of computer storage devices and their characteristics. It covers dedicated, shared, and virtual devices, as well as sequential and direct access storage media like magnetic tapes, disks, optical discs, flash memory, and magneto-optical disks. The key aspects of each storage technology are described, including their read/write processes, data access times, storage capacities, and advantages/disadvantages for different uses.
The document discusses various characteristics and types of computer storage systems. It describes storage media and devices, volatility, access methods, logical vs physical file representations, and common storage technologies like magnetic hard drives, solid state drives, optical discs, flash memory, and network/cloud storage. Hard drive concepts like partitioning, caching and hybrid drives are explained. Details are provided about optical discs, flash memory cards and drives, smart cards, and large-scale storage solutions like RAID and storage servers.
This document provides an overview of secondary storage devices, including magnetic storage devices like magnetic tapes, hard disks, and floppy disks. It also discusses optical storage devices such as compact discs, digital versatile discs, and Blu-ray discs. Finally, it covers flash drives. The document describes the basic components and features of these various storage technologies and how they work to store digital data.
This document is a chapter from a McGraw-Hill textbook about different types of storage devices. It describes magnetic storage devices like hard drives and floppy disks which use magnets to write binary data to iron oxide surfaces. It also discusses optical storage formats like CDs and DVDs that use lasers to read data encoded in pits and lands. Finally, it covers solid state devices such as flash memory drives and smart cards that store data using physical switches instead of magnets or lasers.
This chapter discusses storage devices and technologies. It describes common disk storage options like hard drives, DVD/CD drives, removable drives, and flash drives. Hard drive interfaces like IDE, SATA, SCSI, and SAS are explained. The chapter also covers optical disc technologies like CDs, DVDs, and Blu-Ray discs. Network storage options such as SAN, NAS, cloud storage, and tape backup systems are introduced along with their capacities and features.
This document discusses different types of computer memory including primary memory (RAM and ROM), secondary storage (hard drives, CDs, DVDs, etc.), and cache memory. RAM is volatile and used for temporary storage of data and programs needed to run the computer. ROM is non-volatile and holds the operating system bootstrap loader. Cache memory improves performance by storing frequently used data and instructions closer to the processor. Secondary storage devices include hard drives, optical discs, USB drives, and solid state drives which are used for long-term and offline storage of data.
The document discusses different types of storage devices and media used in computers. It describes how storage is needed to permanently store data and programs since RAM is volatile. The main storage devices discussed are hard drives, solid state drives, optical discs, USB flash drives, and memory cards. It provides details on how each type of storage device works, including characteristics like access time, storage capacity, and the difference between sequential and random access storage. Magnetic storage like hard disks and tapes are also covered.
The document discusses various computer memory and storage devices. It covers RAM, ROM, magnetic storage like hard disks and floppy disks, and optical storage like CDs, DVDs, and Blu-ray discs. It defines key terms related to these storage technologies like volatile vs non-volatile memory, and size units like megabytes, gigabytes, and terabytes. Characteristics of different storage types are explored such as speed, capacity, cost and portability.
This document provides an overview of different storage devices and media. It discusses magnetic storage devices like hard drives, magnetic tapes, and optical media like CDs, DVDs, and Blu-Ray discs. It also covers solid state storage devices like USB flash drives and memory cards. For each type of storage device, it describes their uses, access methods, advantages, and disadvantages. The document aims to explain key concepts around storage to help with revision.
The document discusses various physical storage media used in computers including cache, main memory, flash memory, magnetic disks, optical disks, and magnetic tapes. It classifies storage based on characteristics like speed of access, cost, and reliability. RAID systems are described which provide storage virtualization through techniques like mirroring and striping across disks to improve performance and reliability. Different RAID levels are outlined including RAID 0, 1, 2, 3, 4, 5, and 6.
This document discusses computer memory and storage devices. It describes the main types of memory, including RAM, ROM, PROM, and EPROM. It also outlines various storage devices such as magnetic disks, optical disks, hard disks, floppy disks, CDs, DVDs, and Blu-ray discs. The document explains the characteristics, workings, and capacities of these different memory and storage technologies. It also defines basic units of measurement used for computer components like bits, bytes, kilobytes, megabytes and more.
The document discusses various computer memory and storage devices. It describes RAM and ROM as the main types of memory devices, where RAM is volatile and used for temporary storage, while ROM is non-volatile and can retain data without power. For storage, it outlines magnetic storage devices like hard disks and floppy disks, as well as optical disks like CDs, DVDs, and Blu-ray discs, which allow higher data capacity than magnetic storage. It provides details on the structure and operation of these different memory and storage technologies.
This document discusses different types of storage devices. It describes how magnetic storage devices like hard drives and floppy disks store data using magnets to write binary codes onto metal platters coated with iron oxide. Optical storage devices like CDs and DVDs use lasers to write data onto disks. Solid-state devices store information using physical switches instead of magnets or lasers, making them very fast but more expensive than magnetic devices. Common examples discussed are flash drives, smart cards, and solid-state disks.
Storage provides capacity for files and information through devices like hard disks, while memory provides working space through RAM. Primary storage includes RAM and cache for running the computer, while secondary storage is long-term storage like hard disks. RAM is volatile memory used for running programs, coming in static RAM and dynamic RAM forms. ROM is read-only memory storing basic instructions. Cache memory improves performance by storing frequently used data and instructions. Optical storage includes CDs, DVDs, and Blu-rays, while magnetic storage encompasses floppy disks and hard disks. Flash memory offers portable options like USB drives and solid-state drives.
This document discusses different types of secondary storage devices and their characteristics. It begins by explaining the limitations of primary storage and need for secondary storage. It then classifies commonly used secondary storage devices as sequential-access devices like magnetic tapes and random-access devices like magnetic disks. Specific device details covered include half-inch tape reels, tape cartridges, floppy disks, hard disks, CDs, DVDs, flash drives and memory cards. The document concludes by presenting the storage hierarchy from fastest and most expensive to slowest and least expensive storage.
Secondary storage devices are used to store and retrieve data outside of the computer's main memory. They include internal hard drives and removable media like USB drives, CDs, DVDs, and tapes. Secondary storage saves data permanently, allows portability between devices, and comes in various sizes and formats. Common types discussed are fixed internal hard drives using magnetic disks, removable optical disks like CDs and DVDs, magnetic tapes for backups, and floppy disks which were an early portable storage type but have been replaced by higher capacity devices.
The document discusses computer security and privacy. It covers risks from hardware loss, damage, and failure, and ways to safeguard hardware using locks, encryption, tracking software and backups. It also discusses software piracy, digital counterfeiting, and how they can be prevented. The document outlines privacy concerns regarding databases, profiling, spam and surveillance. It provides tips for protecting personal information and ways individuals can protect their privacy when using computers.
This chapter discusses databases and database management systems. It defines what a database is and the key components like tables, records, and fields. It discusses database concepts like data hierarchy, relationships, and data definition. It also covers database classifications, the most common database models including relational and object-oriented, and how relational databases are designed, created, used and maintained. Finally, it discusses how databases are commonly used on the web.
This document provides an overview of program development and programming languages. It discusses different approaches to program design such as structured programming, object-oriented programming, aspect-oriented programming, and adaptive software development. It also describes the phases of the program development life cycle including problem analysis, program design, coding, debugging and testing. Common programming languages and tools that can facilitate the development process are also covered.
This chapter discusses information systems and the system development life cycle. It defines an information system as a system used to generate information to support organizational users. It describes common types of information systems such as transaction processing systems, decision support systems, and integrated enterprise systems. It also outlines the roles and responsibilities of information technology professionals involved in system development, including systems analysts. Finally, it details the key steps of the system development life cycle, from preliminary investigation and system analysis to system implementation and maintenance.
This chapter discusses e-commerce and how businesses can implement online sales. It covers the advantages and disadvantages of e-commerce for businesses and consumers. Various e-commerce business models are identified, including business-to-consumer, business-to-business, and consumer-to-consumer. Different types of e-commerce websites like manufacturer sites, brokerage sites, and subscription sites are also described. The chapter outlines the steps to implement an e-commerce website including selecting a business model, payment options, website design, sales and marketing strategies, and addressing security issues.
This chapter discusses multimedia and the web. It begins by defining web-based multimedia as the integration of various media types like text, images, video, and sound on web pages. It then discusses the basic multimedia elements of text, images, animation, audio, and video. The chapter also covers designing multimedia web sites, including determining objectives and audience, using flowcharts and layouts, and accessibility considerations. It concludes by outlining the process of developing a multimedia web site, which involves creating multimedia elements, using markup languages like HTML and XML to code pages, and testing and publishing the site.
This document discusses network and internet security. It covers 10 learning objectives on topics like unauthorized access, computer sabotage, identity theft, and protecting personal safety online. Some key points made include that security concerns are prevalent with computer networks and the internet. Examples are given of unauthorized access like hacking, war driving, and packet sniffing. The document also details ways to protect against unauthorized access, such as using access control systems, firewalls, encryption, and virtual private networks.
This document discusses the evolution of the Internet from its origins as ARPANET in 1969 to today's World Wide Web. It describes the various entities that make up the Internet community including users, internet service providers, content providers, infrastructure companies, and government organizations. It also outlines options for connecting to the Internet, such as dial-up, broadband, wireless and mobile connections. Key considerations for selecting a device, connection type, and internet service provider are reviewed.
This document provides an overview of key topics related to computer networks that will be covered in Chapter 7, including defining what a computer network is, common networking applications such as the internet and cellular networks, characteristics of networks such as wired vs wireless and different topologies, how data is transmitted over networks, examples of networking media like twisted pair cable and wireless frequencies, common communication protocols and standards, and networking hardware devices. The chapter will cover networking concepts, technical issues, protocols, and hardware in detail.
This document provides an overview of application software and discusses various types of application programs. It begins by defining application software and describing different types of software ownership rights. It then covers the basics of application software, including the differences between installed and web-based software. The document proceeds to discuss specific types of application software like word processing, spreadsheets, databases, and presentation graphics. It provides details on creating and working with documents in each of these software categories.
The document discusses system software, including operating systems and utility programs. It describes the functions of operating systems such as interfacing with users, booting computers, managing devices and resources, and providing security. Popular operating systems mentioned include Windows, Mac OS, Linux, Android, and iOS. Utility programs are also discussed, including file management programs, backup and restore utilities, disk management, and search tools.
This chapter discusses various input and output devices used with computers. It describes keyboards, pointing devices like mice and touchscreens, as well as scanners, readers and digital cameras that are used to input images, text and other data into computers. Output devices covered include display screens, printers and audio output systems. The chapter provides details on the types, functions and uses of different input/output hardware.
The document discusses the components inside a computer system unit. It describes how data and programs are represented digitally and in binary. The central processing unit (CPU) and memory are located on the motherboard along with buses that connect components. The CPU contains arithmetic, logic, and control units and processes instructions in memory. Expansion slots add functionality. Strategies like multi-core CPUs and faster buses improve performance.
This chapter introduces computers and their role in modern society. It discusses how computers have become integrated into business and personal lives. The chapter defines what a computer is and its basic operations of input, processing, output, storage, and communication. It provides an overview of the history of computers and important milestones. It also defines software and describes the major types of computers including personal computers, servers, mainframes, and supercomputers. Finally, it introduces computer networks and the internet.
This chapter discusses intellectual property rights, ethics, health issues related to computer use, access to technology, and environmental impacts. It covers various types of intellectual property including copyrights, trademarks, patents, and digital rights management. Ethics topics include proper use of copyrighted material, information resources, and addressing issues like digital manipulation. Health sections explore physical risks from improper ergonomics as well as emotional stressors. Access barriers like the digital divide within and between countries are also examined.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
How to Setup Warehouse & Location in Odoo 17 InventoryCeline George
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
How to Manage Your Lost Opportunities in Odoo 17 CRMCeline George
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
How to Make a Field Mandatory in Odoo 17Celine George
In Odoo, making a field required can be done through both Python code and XML views. When you set the required attribute to True in Python code, it makes the field required across all views where it's used. Conversely, when you set the required attribute in XML views, it makes the field required only in the context of that particular view.
How to Build a Module in Odoo 17 Using the Scaffold MethodCeline George
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
How to Fix the Import Error in the Odoo 17Celine George
An import error occurs when a program fails to import a module or library, disrupting its execution. In languages like Python, this issue arises when the specified module cannot be found or accessed, hindering the program's functionality. Resolving import errors is crucial for maintaining smooth software operation and uninterrupted development processes.
2. Learning Objectives
1. Name several general characteristics of storage systems.
2. Describe the two most common types of hard drives and
what they are used for today.
3. Discuss the various types of optical discs available today and
how they differ from each other.
4. Identify some flash memory storage devices and media and
explain how they are used today.
5. List at least three other types of storage systems.
6. Summarize the storage alternatives for a typical personal
computer.
Understanding Computers: Today and Tomorrow, 14th Edition
2
2
3. Overview
1. Examine the characteristics common among all storage
systems.
2. Discuss the primary storage for most personal computers—
the hard drive.
3. Discuss how optical discs work and the various types that are
available today.
4. Discuss flash memory storage systems.
5. Discuss network and online/cloud storage, smart cards,
holographic storage, and storage systems used with large
computer systems.
6. Evaluate storage alternatives for a typical personal computer.
Understanding Computers: Today and Tomorrow, 14th Edition
3
3
4. Storage System Characteristics
• Storage Media and Storage Devices
– Medium
• Hardware where data is stored
• DVD disc, flash memory card, etc.
– Device
• DVD drive, flash memory card reader, etc.
• Medium is inserted into device to be used
– Can be internal, external, or remote
– Storage devices are typically identified by letter
Understanding Computers: Today and Tomorrow, 14th Edition
4
6. Storage System Characteristics
• Volatility
– Storage devices are nonvolatile
• Random vs. Sequential Access
– Random access (direct access) allows data to be retrieved
from any location on the storage medium
– Most storage devices use random access
– Sequential access means retrieval of data can occur only in
the order in which it was physically stored on the storage
medium
• Magnetic tape drive
Understanding Computers: Today and Tomorrow, 14th Edition
6
7. Storage System Characteristics
• Logical vs. Physical Representation
― File
• Anything stored on a storage medium, such as a
program, document, digital image, or song
― Filename
• Name given to a file by the user
― Folder
• Named place on a storage medium
into which files can be stored
Understanding Computers: Today and Tomorrow, 14th Edition
7
9. Storage System Characteristics
– Logical file representation
• Individuals view a document stored as one complete
unit in a particular folder on a particular drive
– Physical file representation
• Computers access a particular document stored on a
storage medium using its physical location or locations
• Types of Storage Technology Used
• Magnetic (conventional hard drives)
• Optical (optical discs)
• Electrons (flash memory media)
Understanding Computers: Today and Tomorrow, 14th Edition
9
10. Hard Drives
• Hard Drive
– Used to store most programs
and data
– Can be internal or external
– Can be encrypted
• Magnetic Hard Drives
– One or more permanently
sealed metal magnetic disks
with an access mechanism and
read/write heads
– Read/write heads magnetize
particles to represent the data’s
0s and 1s
Understanding Computers: Today and Tomorrow, 14th Edition
10
12. Hard Drives
― Hard disks are divided into
• Tracks
– Concentric path on disk where data is recorded
• Sectors
– A small piece of the track
• Clusters
– One or more sectors; smallest addressable area of
a disk
• Cylinders
– Collection of tracks located in the same location on
a set of hard disk surfaces
Understanding Computers: Today and Tomorrow, 14th Edition
12
14. Hard Drives
• Solid State Drives (SSDs)
– Use flash memory
technology
– Use less power and have no
moving parts
– Particularly appropriate for
portable computers and
mobile devices
Understanding Computers: Today and Tomorrow, 14th Edition
14
15. Hard Drives
• Internal and External Hard Drives
– Internal hard drives
• Permanent storage devices located inside the system
unit
• Removed only if a problem develops
– Full-size external hard drives
• Commonly used to transport large amounts of data
from one computer to another
• Portable external hard drives are smaller and easier to
transport
• Most connect with a USB connection although some
may be wireless
Understanding Computers: Today and Tomorrow, 14th Edition
15
17. Hard Drives
• Hard Drive Speed, Disk Caching, and Hybrid Hard Drives
– Disk access time
• Total time that it takes for a hard drive to read or write
data
• Consists of seek time, rotational delay, and data
movement time
– SSDs don’t require seek time or rotational delays
– Disk cache
• Memory used in conjunction with a magnetic hard
drive to improve system performance
• Can be a dedicated part of RAM or memory chips on a
circuit board inside the hard drive case
Understanding Computers: Today and Tomorrow, 14th Edition
17
18. Hard Drives
– Hybrid hard drive
• Combination of
flash memory and
magnetic hard drive
• Uses flash memory
for cache
• Allows encryption
to be built into the
drive
Understanding Computers: Today and Tomorrow, 14th Edition
18
19. Hard Drives
• Hard Drive Partitioning and File Systems
– Partitioning
• Divides the physical capacity of a single drive logically
into separate areas, called partitions
• Partitions function as independent hard drives
• Referred to as logical drives
• Increase efficiency (smaller drives use smaller clusters)
– Partitions used to
• Create a recovery partition
• Create a new logical drive for data
• Create a dual boot system
Understanding Computers: Today and Tomorrow, 14th Edition
19
20. Hard Drives
– File system
• Determines the cluster size, maximum drive size, and
maximum file size
– FAT, FAT32, and NTFS
Understanding Computers: Today and Tomorrow, 14th Edition
20
21. Hard Drives
• Hard Drive Interface Standards
– Determine how a drive connects to the computer
– Common standards
• Parallel ATA (PATA) - older, slower standard
• Serial ATA (SATA)
• eSATA
• SCSI and the newer serial attached SCSI (SAS)
• Fibre Channel
• Fibre Channel over Ethernet (FCoE)
• Internet SCSI (iSCSI)
Understanding Computers: Today and Tomorrow, 14th Edition
21
22. Quick Quiz
1. Of the following three options, the storage media that would hold
the most data is a(n) _______________________.
a. internal hard drive
b. USB flash memory drive
c. portable hard drive
2. True or False: Hard drives typically contain more than one metal
hard disk.
3. The circular rings on a magnetic disk on which data is stored are
called ________________________.
Answers:
1) a; 2) True; 3) tracks
Understanding Computers: Today and Tomorrow, 14th Edition
22
23. Optical Disks and Drives
• Optical Disc Characteristics
– A type of storage read from and written to using laser
beams
– Today’s standard for software delivery
– Divided into sectors like magnetic discs but use a single
spiral track (groove)
– Have a relatively large capacity and are durable
– Used for backup purposes and for storing and transporting
music, photos, video, etc.
Understanding Computers: Today and Tomorrow, 14th Edition
23
24. Optical Discs and Drives
– Representing Data on an Optical Disc
• Read-only optical disc
– Surface of disc is molded or stamped
• Recordable or rewritable disc
– Optical drive is used and the reflectivity of the disc
is changed using a laser to represent the data
• Data is stored in 0s and 1s
– Pits and lands are used to represent 1s and 0s
– The transition between a pit and a land represents
a 1; no transition represents a 0
Understanding Computers: Today and Tomorrow, 14th Edition
24
25. Optical Discs and Drives
Understanding Computers: Today and Tomorrow, 14th Edition
25
26. Optical Discs and Drives
– Optical Drives
• Three categories of discs: CD, DVD, or Blu-Ray Disc (BD)
• Can be read-only, recordable, or rewritable
• Almost always downward compatible
• Can support single or dual layer discs
• Recording data onto disc is called burning
• Can be internal or external drives
– External drives typically USB
Understanding Computers: Today and Tomorrow, 14th Edition
26
27. Optical Discs and Drives
– Optical Disc Shapes, Sizes, and Capacities
• Standard size is 120-mm (about 4.7 inches)
– Mini discs are smaller—80-mm
• Theoretically can be made into various shapes—hearts,
triangles, irregular shapes, or a hockey-rink shape
– Patent battle exists about changing optical disc
shapes
– None of these different shapes are currently
available
Understanding Computers: Today and Tomorrow, 14th Edition
27
28. Optical Discs and Drives
• Major advantage is their large capacity
– CD discs are normally single layer and hold 650 or
700 MB
– DVD discs hold 4.7 GB (single-layer) or 8.5 GB (duallayer
– BD discs hold 25 GB (single-layer) or 50 GB (duallayer
– Discs can also be double-sided
– Researchers continually work to increase the
capacity of optical discs
Understanding Computers: Today and Tomorrow, 14th Edition
28
29. Optical Discs and Drives
Understanding Computers: Today and Tomorrow, 14th Edition
29
30. Optical Discs and Drives
• Read-Only Optical Discs: CD ROM, DVD ROM, and BD-ROM
– Can be read from, but not written to, by the user
• CD-ROM (compact disc read-only memory)
• DVD-ROM (digital versatile disc read-only memory)
• BD-ROM (Blu-Ray disc read-only memory)
– Normally come pre-recorded
• Software programs
• Clip art and other graphics
• Music
• Movies
• Games (UMD, Wii, Xbox, etc.)
Understanding Computers: Today and Tomorrow, 14th Edition
30
31. Optical Discs and Drives
• Recordable Optical Discs: CD-R, DVD-R, DVD+R, BD-R Discs
– Can be written to, but cannot be erased and reused
• Uses phase change technology
– Heating and cooling process is used to change the
reflectivity of the disc
• Capacities are identical to the read-only discs
• CD-R discs – recordable CDs
• DVD-R/DVD+R discs can be dual-layer
• BD-R can be dual-layer
― Used for back up, sending large files to others, creating
custom music CDs, storing home movies, etc.
Understanding Computers: Today and Tomorrow, 14th Edition
31
32. Optical Discs and Drives
Understanding Computers: Today and Tomorrow, 14th Edition
32
33. Quick Quiz
1. The capacity of the typical CD disc is ______________________.
a. 50 GB
b. 650 MB
c. 4.7 GB
2. True of False: A DVD-RW disc can be written to and rewritten to.
3. The tiny depressions, dark areas, or otherwise altered spots on an
optical disc that are used to represent data are called
______________________.
Answers:
1) b; 2) True; 3) pits
Understanding Computers: Today and Tomorrow, 14th Edition
33
34. Flash Memory Storage Systems
• Flash Memory
– Non-volatile memory chips used for storage by the
computer or the user
– Used in SSDs, hybrid hard drives, and USB flash drives
• Embedded Flash Memory
– Flash memory chips embedded into products, such as
Portable digital media players
Digital cameras
GPS devices
Handheld gaming devices
Mobile phones
Sunglasses
Wristwatches
Tablet computers Smartphones
Understanding Computers: Today and Tomorrow, 14th Edition
34
35. Flash Memory Storage Systems
Understanding Computers: Today and Tomorrow, 14th Edition
35
36. Flash Memory Storage Systems
• Flash Memory Cards and Readers
– Flash memory card
• A small card containing one or more flash memory
chips, controller chips, and metal contacts to connect
the card to the device or reader with which it is being
used
• Available in various formats:
CompactFlash
Secure Digital (SD)
xD Picture Card
Memory Stick
Secure Digital High Capacity (SDHC)
MultiMedia Card (MMC)
Secure Digital Extended
Capacity (SDXC)
These formats are not interchangeable
Understanding Computers: Today and Tomorrow, 14th Edition
36
37. Flash Memory Storage Systems
Understanding Computers: Today and Tomorrow, 14th Edition
37
38. Flash Memory Storage Systems
– General-purpose flash memory card
• Appropriate for most applications
– Specialized flash memory cards
• Professional flash memory cards
– Designed for professional photographers
• Gaming flash memory cards
– Designed for gaming consoles
• HD flash memory cards
– Designed for capturing and transferring high
definition video
• Netbook flash memory cards
Understanding Computers: Today and Tomorrow, 14th Edition
38
39. Flash Memory Storage Systems
• USB Flash Drives
– Sometimes called flash memory drives, jump drives, or
thumb drives
– Small storage devices that plug into and are powered by a
USB port and contain flash memory storage
– Available in a range of sizes, colors, and appearances
– May also be used to lock a computer and to issue Web site
passwords
– Can include biometric features, such as a built-in
fingerprint reader
Understanding Computers: Today and Tomorrow, 14th Edition
39
40. Flash Drive Storage Systems
Understanding Computers: Today and Tomorrow, 14th Edition
40
41. Other Types of Storage Systems
• Network Storage and Online/Cloud Storage Systems
– Remote storage
• Using a storage device not directly connected to
the computer being used
• Accessed through the internet or through a
network
– Network storage
• Via a local network
Understanding Computers: Today and Tomorrow, 14th Edition
41
42. Other Types of Storage Systems
– Network attached storage (NAS)
• Connected directly to a network
• High performance storage for computers
connected to a network
– Storage area network (SAN)
• Separate network of hard drives or other storage
devices which are attached to the main network
Understanding Computers: Today and Tomorrow, 14th Edition
42
43. Other Types of Storage Systems
Understanding Computers: Today and Tomorrow, 14th Edition
43
44. Other Types of Storage Systems
– Online storage or cloud storage
• Accessed via the Internet
– Via Web sites (Flickr, Facebook, Google Docs, etc.)
– Via online storage sites (Box.net, SkyDrive, etc.)
– Growing in importance because more and more
applications are web-based
– Increasing being used for back up purposes
– Many web sites providing online storage offer it
free
Understanding Computers: Today and Tomorrow, 14th Edition
44
45. Other Types of Storage Systems
Understanding Computers: Today and Tomorrow, 14th Edition
45
46. Other Types of Storage Systems
– Smart Cards
• Credit card-sized piece of plastic that contains some
computer circuitry (processor, memory, and storage)
• Stores small amount of data (about 64 KB or less)
• Commonly used to store prepaid amounts of digital
cash or personal information
• Smart card readers are built into or attached to a
computer, keyboard, vending machine, or other device
• Some smart cards store biometric data
• Can be used in conjunction with encryption and other
security technologies
Understanding Computers: Today and Tomorrow, 14th Edition
46
47. Other Types of Storage Systems
Understanding Computers: Today and Tomorrow, 14th Edition
47
48. Other Types of Storage Systems
– Holographic storage
• Emerging type of 3D storage technology
• Uses multiple blue laser beams to store data in three
dimensions
– Reference beam
– Signal beam
• Possible applications
– High-speed digital libraries
– Image processing for medical, video, and military
purposes
– Any other applications in which data needs to be
stored or retrieved quickly in large quantities but
rarely changed
Understanding Computers: Today and Tomorrow, 14th Edition
48
49. Other Types of Storage Systems
Understanding Computers: Today and Tomorrow, 14th Edition
49
50. Other Types of Storage Systems
– Storage Systems for Large Computer Systems
• Storage server
– Hardware device containing multiple high-speed
hard drives connected to the computer system or
network
– Most are based on magnetic hard discs
• Businesses have to store tremendous amounts of data
– Storage needs will increase 50% annually through
2014
– Business data
– Employee and customer data
– E-discovery data
Understanding Computers: Today and Tomorrow, 14th Edition
50
51. Other Types of Storage Systems
– RAID (redundant arrays of independent discs)
• Method of storing data on two or more hard drives that
work together to do the job of a larger drive
• Mostly used to protect critical data on large storage
systems
• Usually involves recording redundant copies of stored
data
• Helps to increase fault tolerance
Understanding Computers: Today and Tomorrow, 14th Edition
51
52. Other Types of Storage Systems
• Different levels of RAID:
– RAID 0 = disk striping (spread files over two or more
hard drives)
– RAID 1 = disk mirroring (duplicate copy)
– Other level use a combination or striping and
mirroring
• Drobo system
– New RAID storage system
– Much easier to use than previous systems
– Offers continuous data redundancy
Understanding Computers: Today and Tomorrow, 14th Edition
52
53. Other Types of Storage Systems
Understanding Computers: Today and Tomorrow, 14th Edition
53
54. Other Types of Storage Systems
– Magnetic Tape Systems
• Plastic tape with a magnetizable surface that stores
data as a series of magnetic spots
• Primarily used for backup and archival purposes
• Sequential access only
• Low cost per megabyte
• Most tapes today are in the
form of cartridge tapes
Understanding Computers: Today and Tomorrow, 14th Edition
54
55. Evaluating Your Storage
Alternatives
• Product Characteristics to Consider:
– Speed
– Compatibility
– Storage capacity
– Convenience
– Portability
• Most Users Require:
– Hard drive
– Recordable or rewritable optical drive
– Flash memory card reader
– USB port(s)
Understanding Computers: Today and Tomorrow, 14th Edition
55
56. Quick Quiz
1. An online photo sharing site is an example of
______________________.
a. RAID
b. remote storage
c. holographic storage
2. True of False: Flash memory storage systems are called solid-state
storage systems because they are nonvolatile.
3. A type of sequential storage that sometimes used today for backup
purposes is _____________.
Answers:
1) b; 2) False; 3) magnetic tape
Understanding Computers: Today and Tomorrow, 14th Edition
56