chapter+8+study+guide


 * Chapter 8 Study Guide**


 * Computer Hardware****two components: hardware software**
 * ***circuit-a switch- When the switch is on the power travels through the circuit. When the switch is off the power can not travel through the circuit. So computers use patterns of circuits to represent numbers and letters and operations on those letters and numbers.**
 * **ROM stands for Read Only Memory and is memory that doesn’t change**
 * **RAM or volatile memory is memory that changes. RAM is short for random access memory**
 * **Memory and storage are measured in units called bits and bytes**
 * **A bit is one circuit. It comes from the words binary digit.**
 * **A byte is like an 8 character code for a letter**
 * **special assistive devices to allow people with many different types of disabilities to more easily use the computer such as touch screen and head wands or switches.**
 * **Resolution is the term used to describe the number of pixels - the higher the resolution the more pixels**
 * **Resolution describes the quality of the image - the higher the resolution the sharper the printed image**


 * mother board: heart of the computer where most circuits are located made up of chips everything connects to it**
 * CPU: most important chip on mother board Central Processing Unit does actual work of computer system**
 * clock speed: how fast a processor can process commands**
 * MEMORY: two types:** **ROM: Read Only Memory- determines computing power- does NOT change RAM: Random Access Memory-volatile memory- does change**
 * Gig: measurement unit**
 * The basic unit in a binary system is the bit (Binary digIT).**
 * PERIPHERALS:3 types-input (keyboard, mouse, assistive devices, microphones, cameras)output (monitors, speakers, printers, projection devices)storage :internal- hard drive, network drive external-floppy, flash drive, external hard drive, CD, DVD**
 * PORTS: (physical connection to the motherboard on the back of the case)USB Fire wire Monitor- VGA, S-Video PCI**