2ND QUARTER

input unit

any data or instructions entered into the memory of a computer

keyboard, ball mouse, and optical mouse

what are the types of input units?

keyboard

to enter information into computers

QWERTY keyboard

what is the standard keyboard called?

ball mouse

operated by rolling its ball across a flat surface

optical mouse

uses a light emitting diode to by detecting the changes in the reflected light

output unit

supplies information and results of computation to the outside world

monitor

where you can view what you are working on

printer

produces a hard copy of the information

memory or storage devices

all computers need this to hold data

main memory of primary memory

a temporary area for holding data or for when the program is still running

random accessed memory

what does RAM mean?

RAM

if the computer turn off, all data will be lost

static RAM

the memory retains as long as power is supplied

dynamic RAM

need continuous refreshing to maintain data

read only memory

what does ROM mean?

ROM

we can read, but can not write on it, and it is used to store some firmware programs

programmable read only memory

what does PROM mean?

erasable and programmable read only memory

what does EPROM mean?

electrically erasable and programmable read only memory

what does EEPROM mean?

backing storage or secondary memory

permanent memory of the system

magnetic disk

stores the data in the form of magnetic directions

hard disk

acess to data is faster then floppy disks

floppy disk

a plastic disk coated with iron oxide

optical disk

read operations is done using a low powered laser beam

compact disk- read only memory

what does CD-ROM mean?

compact disk- recordable

what does CD-R mean?

compact disk- rewindable

what does CD- RW mean?

digital versatile disk- read only memory

what does DVD- ROM mean?

digital versatile disk- random access memory

what does DVD-RAM mean?

processor or CPU

the brain of the computer and controls the entire system

arithmetic and logic unit

what does ALU mean?

ALU

where the actual execution of the instructions takes place

control unit

what does CU mean?

CU

acts as a central nervous system