Chapter 1 Computer Hardware

Front 1

Capacitor

Back 1

a semiconductor that temporarily stores electricity

Front 2

Semiconductor

Back 2

microscopic parts that partially conduct or sometimes conduct electricity

Front 3

Diode

Back 3

a semiconductor that allows electricity to flow in only one direction.

Front 4

LED

Back 4

acronym for light emitting diode; a diode that emits light whenelectricity is flowing through it.

Front 5

Resistor

Back 5

a semiconductor that resists the flow of electricity. A resistor isoften used to protect other parts of a computer from surges in electricity

Front 6

Transistor

Back 6

a semiconductor with two inputs and one output called the drain. A smallcurrent on the center wire of the transistor controls a larger current thatflows on the two outer wires. A transistor can be used as an amplifier or anautomated switch with the small electric current input controlling the largerinput and output current.

Front 7

Integrated circuit

Back 7

a circuit composed of many (possibly billions) semiconductors etched ona small piece of silicon; sometimes called a computer chip

Front 8

hardware

Back 8

the physical parts of a computer, such as the keyboard, mouse, CPU, harddrive, memory, monitor, and printer

Front 9

Power supply

Back 9

an electric circuit that converts the electricity coming from an outletin the wall, usually 115 volts, 60 Hertz alternating current (AC), intoelectricity that a computer can use, something like 3.3 volts direct current(DC).

Front 10

Keyboard

Back 10

an input device that allows a user to enter data into a computer bypressing keys.

Front 11

Motherboard

Back 11

the main circuit board to which the other parts of a computer areattached.

Front 12

Bus

Back 12

the wires and integrated circuits that transfer data across themotherboard from one component to another

Front 13

BIOS

Back 13

acronym for basic input and output system; usually flash memoryinstalled on the motherboard that contains instructions the CPU executes when acomputer is started.

Front 14

Cache

Back 14

a small amount of fast memory that temporarily stores data andinstructions and is often located on the CPU. The cache contains a partial copyof the contents of main memory so that when the CPU needs data for acalculation, the CPU can get the data from the cache and does not have to waitfor the data to come over a bus from main memory. Cache memory is volatile.

Front 15

volatile

Back 15

when a computer is turned off or the electricity is removed, thecontents are lost

Front 16

Main memory

Back 16

integratedcircuits that temporarily store data and instructions for the CPU; sometimescalled random access memory (RAM). Main memory is volatile.

Front 17

Hard drive

Back 17

stores data semi-permanently usually on a spinning platter wheremicroscopic spots have been magnetized to store data. A hard drive is non-volatile. Figure 5 shows a hard drive with its cover removed to exposethe platter and the head that moves above the platter and magnetizes microscopicspots on the platter.

Front 18

non-volatile

Back 18

when a computer is turned off, the contents arepreserved

Front 19

CD or DVD drive

Back 19

reads and writes data semi-permanently to a disc using a laser. Compactdiscs (CD’s) and digital versatile disks (DVD’s) are non-volatile

Front 20

Jump, thumb, or flash drive

Back 20

semi-permanent memory that can be read, written, and erasedelectrically. Jump drive, thumb drive, and flash drive are different names forthe same type of memory device which stores data in flash memory. A solid statehard drive does not store data on a platter like a regular hard drive but insteadstores data in flash memory. Flash memory is non-volatile.

Front 21

Monitor

Back 21

an output device that displays messages, images, etc. for a user to see.

Front 22

A quad core CPU with a clock speed of 2.5 gigahertz is designed tocomplete how many instructions per second?

Back 22

10 billion (4 * 2.5 gigahertz)

Front 23

bit

Back 23

an abbreviation for binary digit. A binary digit is a column in abinary number where either 0 or 1 can appear.

Front 24

nibble

Back 24

four bits joined together to form a binary number. (The name nibble is aninside computing joke because a nibble is half of a byte)

Front 25

byte

Back 25

eight bits joined together to form a binary number.

Front 26

1. kilobyte

2. megabyte

3. gigabyte

4. terabyte

5. petabyte

6. exabyte

Back 26

– 1024 (210) bytes

– 1,048,576 (220) bytes

– 1,073,741,824 (230) bytes

– 1,099,511,627,776 (240) bytes

– 1,125,899,906,842,624 (250) bytes

– 1,152,921,504,606,846,976 (260) bytes

Front 27

What unit measures clock speed?

Back 27

In hertz.

Front 28

A single hertz is how many cycles per second?

Back 28

One cycle.

Front 29

What is a cycle?

Back 29

from any point in the pulse to where the pulse repeats.

Front 30

hertz

Back 30

a unit of frequency equal to one cycle per second.

Front 31

megahertz

Back 31

one million cycles per second

Front 32

gigahertz

Back 32

one billion cycles per second

Front 33

micro or personal computer

Back 33

a computer designed to be used by only one person at a time, such as asmart phone, tablet computer, laptop computer, or desktop computer.

Front 34

workstation

Back 34

a powerful computer designed to be used by one person at a time and usedto perform engineering, scientific, and medical tasks such as designingairplane parts.

Front 35

mainframe

Back 35

a very powerful computer designed to be used by many people at the sametime to perform business or scientific tasks.

Front 36

Computer software

Back 36

a list of instructions that the computer hardware executes

Front 37

Application

Back 37

computer software that someone uses to accomplish a specific task,such as write a letter, balance an account, watch a movie, or play a game.Examples of applications include Microsoft Word and Excel, Google Chrome, andiTunes.

Front 38

Operating system

Back 38

computer software that manages the hardware and isolates theapplications from the hardware so that the applications do not have to interactdirectly with the hardware. Examples of computer operating systems includeMicrosoft Windows, Mac OS X, VMS, Linux, HP-UX, and Solaris

Front 39

ASCII

Back 39

an acronym for American Standard Code for Information Interchange;a coding system (essentially a table) with 128 rows that assigns a number toeach English letter and common punctuation symbol. See asciitable.com

Front 40

Unicode

Back 40

a very large coding system that includes ASCII and assigns a number tosymbols from many languages, such as English, Portuguese, Greek, Hebrew,Arabic, and Tagalog.