Hard disk is a secondary and permanent storage device in the computer.
It stores large amount of data. It is a solid state storage device.
Reading and writing speed is high.
HDD are available from 1 GB to several TB.
Hard disk is a secondary and permanent storage device in the computer.
It stores large amount of data. It is a solid state storage device.
Reading and writing speed is high.
HDD are available from 1 GB to several TB.
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
Course 102: Lecture 26: FileSystems in Linux (Part 1) Ahmed El-Arabawy
This lecture introduces some concepts about FileSystems in Linux.
Video for this lecture on youtube:
http://www.youtube.com/watch?v=9jj1QOokACo
Check the other Lectures and courses in
http://Linux4EnbeddedSystems.com
or Follow our Facebook Group at
- Facebook: @LinuxforEmbeddedSystems
Lecturer Profile:
Ahmed ElArabawy
- https://www.linkedin.com/in/ahmedelarabawy
Disk Management through the Computer ManagementAnshGoyal32
Disk Management refers to the process of managing and organizing computer storage devices, such as hard drives and solid-state drives. It involves tasks like creating partitions, formatting drives, assigning drive letters, and managing volumes. Disk Management is a critical aspect of maintaining and optimizing your computer's storage space.
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
2. Chapter 10 Objectives
• Understand magnetic and optical storage
• Explain cylinders, heads, tracks, and
sectors
• Understand low-level and high-level
formatting
• Explain principles of partitioning
• Choose an appropriate file system for the
OS to be installed
3. How Disks Store Data
• Magnetic or optical
• Based on transitions
– Electrical: positive or negative
– Optical: pit or land
5. Optical Storage
• CD, DVD
• Change between pit (less reflective) and
land (more reflective)
6. Disks Versus Drives
• Disk: Platters that store data
• Drive: Mechanism that spins and reads
platters
• Hard disk drive: integrated disk and drive
• Floppy and CD: separate disk and drive
7. How Disk Space is Organized
• Heads: Read-write mechanisms, one for
each side of each disk platter
8. How Disk Space is Organized
• Tracks: Concentric rings on a platter
9. How Disk Space is Organized
• Cylinders: The same track on a stack of
platters and sides
10. How Disk Space is Organized
• Sectors: Sections of a track created by
radial lines from the center of the disk
12. Zoned Recording and Sector
Translation
• Zoned Recording: Fewer sectors in center
of disk than at outer rings
• Sector Translation: Conversion between
physical sectors and logical ones needed
to interface with PC
14. CD-ROM Drive BIOS Support
• Auto (Recommended)
• CD-ROM
• ATAPI Removable
• IDE Removable
15. BIOS Translation Methods
• Standard CHS: Cylinders, Heads, Sectors
• Extended CHS (ECHS, also called Large)
• Logical Block Addressing LBA
16. Enhanced BIOS Services for Disk
Drives
• A BIOS feature, not a drive feature
• Released in 1998
• Gives the BIOS the capability to recognize
large drive sizes (over 8.4 GB)
• Primary reason why very old PCs cannot
see large new drives
• Requires a BIOS update for motherboard
or add-on BIOS utility from drive maker
17. Data Transfer Modes
• DMA: Direct Memory Addressing
– Regular and bus mastering
• PIO: Programmed Input/Output
– PIO modes 0 through 4
• UltraDMA (Ultra ATA)
– Modern standard for drive interfaces
– Makes regular DMA and PIO obsolete
– Much faster (33MB/sec to over 150MB/sec)
18. Disk Partitions
• Physical drive can be divided up
– Primary partition
– Extended partition
• Each partition can have one or more
logical drives
– Primary partition can have only one drive
letter
– Extended partition can have multiple drive
letters
21. Master Boot Record
• Contains information about the physical
drive’s partitions
• Written to the first sector of the first
cylinder of the first head
• Persists no matter what high-level
formatting is done to the drive
22. Clusters
• Groups of sectors that are addressed as a
group
• Makes storage access quicker since there
are fewer units to address
• Allows larger drives to be addressed
• Wastes some space when cluster is not
completely full
• Larger clusters are more wasteful
23. Default Cluster Sizes
• Each file system has its own default
cluster size rules (FAT16, FAT32, NTFS)
• Cluster size can vary from 1 to 64 sectors
• Generally, smaller drive has smaller
cluster size
• Refer to Tables 10.1, 10.2, and 10.3 in
textbook
25. FAT Formatting
• Creates the volume boot record:
– Every logical drive has one
– Holds information about the partition
– Stores the boot files if a bootable drive
– Written to the first sector of the logical disk
(the boot sector)
– At startup, OS looks to the boot sector to see
if it contains startup files
26. FAT Formatting
• Creates the File Allocation Table
– Small database
– Two copies of it, for redundancy
– Tracks only the first cluster of each file
– Tracks only files and folders in the root
directory
27. FAT Formatting
• Reads information from low-level format
about physical defects to avoid in disk
surface
• Creates the root directory
– Top-level folder
– All others are placed here
28. FAT16 versus FAT32
• FAT16
– Original FAT file system
– Uses 16-bit binary numbers to identify each
cluster
• FAT32
– Improved version
– Uses 32-bit binary numbers to identify each
cluster
– Drive sizes can be larger because there are
more numbers available for cluster IDs
29. OS Compatibility of FAT
• FAT16:
– All MS-DOS and Windows versions
• FAT32:
– No support in MS-DOS, Windows NT 4.0, or
Windows 95
– Windows 95C provides limited support (no
conversion utility)
– Windows 98 and higher provide full support
30. NTFS
• New Technology File System
• Developed for Windows NT (NTFS 4)
• Improved for Windows 2000 and higher
(NTFS 5)
• 32-bit file system
• More sophisticated security permissions
• Encryption (NTFS 5)
31. NTFS Features
• Volume Boot Record
– Equivalent to Volume Boot Record in FAT32
• Master File Table
– Equivalent to File Allocation Table
• System Files
– No stand-alone command interpreter
– User interface separate from OS kernel
32. OS Compatibility of NTFS
• No support in MS-DOS or 9x versions of
Windows
• NTFS 4 supported in Windows NT 4.0
• NTFS 5 supported in Windows 2000 and
XP
• Conversion done automatically when
upgrading from NT 4.0 to 2000 or XP