Box like case that houses the electronic components Made out of metal or plastic Protects the electronic components The System Unit
The System Unit The System Unit is a box-like case made from metal or plastic that houses the computer electronic components a computer uses to process data. All types and sizes of computers have a system unit.
Motherboard CPU=Central Processing Unit Memory Expansion slots Expansion cards Removable memory devices Components of the System Unit
Central Processing Unit=most important chip in the motherboard CPU=carries out the basic instructions that operate a computer Also referred to as the processor CPU
Directs traffic with in the CPU Repeats 4 basic operations: Fetch=obtaining instruction from memory decoding=translating instructions into commands Executing=carries out commands Storing=writes the result into memory Control Unit
With in the control unit there is a system clock System clock=controls the timing of all computer operations Clock speed= measured in GHz Giga=one billion Hertz=per second cycle 4 GHz= FOUR Billion clock cycles or ticks in ONE second!! System Clock
The components of the system unit include the motherboard, CPU, memory and ports and connectors. Motherboard RAM = Random Access Memory RAM is Volatile, which means data stored in RAM are erased when the power to the computer is turned off. CPU Process ROM= Read-only Memory ROM is nonvolatile because it retains its contents even when the power is turned off. Ports and Connectors
Volatile=lost when the computer turns off (RAM) Nonvolatile=not lost (ROM) RAM=Random Access Memory The more RAM a computer has the more programs and files it can work on at once ROM=Read Only Memory: stores info and instructions that do NOT change. 2 Types of Memory
Humans count with the decimal system which is between 0 and 9 A computers job is to process data electronically Understands only two states: On & OFF; this is referred to as digital. These two states are represented by electronic circuits represented by 1 or 0 Computers use BINARY=2 digits Data Representation
Binary Digit Bit=Binary DigiT The on or off value is represented by a bit Represents the smallest unit of data the computer can handle Not informative by itself but 8 bits = a byte Provides combinations of 0s and 1s Creates over 256 characters
American Standard for Information Interchange Most widely used coding scheme Make it possible for humans to interact with a machine that uses only ones and zeros or BITS Happens so fast http://www.brainpop.com/technology/computersandinternet/binary/ ASCII
What is Input
Any item entered into the memory of a computer.
It can be categorized in four types:
Data- is a collection of unprocessed items. Commands- is an instruction given to a computer program.
What are Input Devices?
Any hardware component that allows you to enter data, programs, commands, and user responses into a computer.
Input devices include:
Scanners and reading devices
Audio and video input devices
Input devices for students with special needs
A popular keyboard used in k-12 classrooms is a wireless keyboard. It is a battery-operated device that transmits data using wireless technology, such as radio waves. Digital cameras allows you to take pictures and store the images digitally instead of on traditional film.
What is Output
Data that has been processed into a useful form called information.
Four common types of output are:
Text- consist of characters that that are used to create words, sentences, and paragraphs. Graphics- are digital representations of nontext information, such as images, drawing, charts, pictures, and photographs. Audio- is any music, speech, or other sound that is stored and produced by the computer. Video- consist of photographic images that are played back at speeds that provide the appearance of full motion in real time.
What Are Output Devices? Display Devices Printers Any computer component capable of conveying information to a user. This includes: Multifunction Devices Data Projectors Facsimile Machines Speakers, Headphones, and Earphones
Display Devices The core of most monitors is made up of a cathode ray tube (CRT) A pixel is a single point in an electronic image
What is Storage? Storage stores data, instructions, and information when they are not being Processed. Storage Media and Devices Magnetic Disks Mini Mobile Storage Devices Optical Disc
A storage medium that consists of a flat round portable disc made of metal, plastic and lacquer that is written to and read from a laser CDs & DVDs R=recordable CD-RW CD-R CD-ROM DVD=digital with much larger storage capabilities Optical Discs
Universal Serial Bus Port can connect up to 127 different devices with a single connector Including: mouse, printer, digital camera, media players, smart phones etc. http://www.brainpop.com/technology/computersandinternet/datastoragedevices/ USB
Open Microsoft Word Create a table for a database Insert header with name Footer with date 4 Columns labeled: Web-site, address/URL summary, uses/ideas 10 Rows: Lab 2 Web-site Database