Tutorial: Computer Hardware Terminology
Dr.
Thomas E. Hicks
Computer Science
Department
Trinity University
Hardware: the physical devices and components associated
with the computer.
Bit: a unit of information storage capacity in
computer memory; it is sufficient to store either a 0 or a 1. It
is short for Binary Digit.
Byte: the amount of space necessary to store one
character; usually eight bits.
ASCII: American Standard Code for Information Interchange.
A standard for defining codes for information exchange between equipment
produced by different manufacturers. (collating sequence)
Mouse: a surface device which an operator can manipulate
in order to control a pointer image on the computer system.
Monitor: a hardware device used to project a visual
image into the processing of a computer system. It is the most common
computer output device.
Keyboard: a most common hardware device used to
input information and commands into a computer system.
Power Supply: converts AC voltage to low-voltage
DC. The output is tightly regulated to keep noise pulses and voltage variations
from upsetting the computer's circuits.
Mother Board: a large circuit board into which
can be plugged a number of smaller boards, or circuit elements. This
board becomes the backbone of a computer system.
Microprocessor: a single semiconductor chip or
a small number of chips that contains the arithmetic and control logic
circuitry necessary to perform the operations of a computer.
ALU: Arithmetic Logic Unit. The mathematical circuitry
necessary to perform the operations of a computer.
CPU: Central Processing Unit. The control circuitry
necessary to perform the operations of a computer.
IC Chip: Integrated Circuit Chip. A complex electronic
circuit fabricated on a simple piece of material, usually a silicon.
RAM: Random Access Memory. A memory chip used for
the main memory of a microcomputer. Application software will both store
and retrieve information from this type of chip.
ROM: Read Only Memory. A memory chip on which a
series of instruction have been permanently stored. This type of chip might
store a copy of your favorite word processor or spreadsheet on your laptop
computer.
Bus: a channel or path for transferring data and
electrical signals.
Floppy Drive: a computer storage read/write device,
usually of minimal capacity, which accepts multiple surfaces. Data on these
surfaces may be randomly accessed. The high density, double sided floppy
disks of today hold 1.4 MB of data.
Hard Drive: a computer storage read/write device,
usually of substantial capacity, which has fixed/permanent surfaces. Data
on these surfaces may be randomly accessed. Hard drives hold as little
as 10 MB and as much as several GB.
Tape Drive: a computer storage read/write device,
usually of substantial capacity, which has one surface. Data on this surfaces
must be sequentially accessed. It is used primarily for backup purposes.
Tape drive access is slow!
CD Rom Drive: a computer storage read and/or read/write
device, always of substantial capacity, which has one surface. Data on
this surface may be randomly accessed. The optical disk containing digitized
information uses the same technology as the musical CD. Most of the compact
disks used by computers are 4.7 inches and hold as much as 780 MB. The
CD drive uses laser technology to read and write to the drive.
SIMM Chip: a Single In-Line Memory Module that
contains random access memory (RAM) for the computer. Older SIMM chips
contain 30 pins and the newer SIMM chips contain 72 pins. SIMM modules
contain as little as 256 KB and as much as 128 MB.
Modem: a data communication device that enables
computers to communicate via telephone lines. The term modem was constructed
from the terms MOdulate and DEModulate. Modulation translates digital data
into analog data. Analog data can be transferred along the phone line.
Demodulation translates analog data into digital data. Single phone line
modems speeds range from 1200 baud to 33,600 baud.
Format Disk: the process of laying out a structure
on the disk that will enable the disk to receive information. IBM PC's
use a different disk format from either the Macintosh or UNIX systems.
IBM PC, Macintosh, and UNIX disk formatting divides the disk into sectors,
tracks, and blocks.
Track: ring-shapped portion of a floppy/hard disk
surface. See [a] below!
Sector: pie-shapped portion of a floppy/hard disk
surface. See [b] below!
Block: rectangular-shapped portion within one track
of one sector of a floppy/hard disk surface. See [c] below!
Input Devices: those devices that provide input
to the computer. Examples of input devices would be keyboard, light pen,
graphics tablet, bar code reader, mouse, scanner, digital camera, floppy
drive, hard drive, CD rom drive, zip drive, electronic keyboard (music),
microphone, A to D (analog to digital) devices/sensors, touch screen monitor,
etc.
Output Devices: those devices that receive output
from the computer. Examples of output devices would be traditional monitor,
floppy drive, hard drive, CD rom drive, zip drive, speakers, printers,
A to D (analog to digital) devices/sensors, touch screen monitor, photo
maker, transparency maker, etc.
Kilobyte. (~ a thousand bytes)
MB: Megabyte. (~ a million bytes)
GB: Gigabyte. (~ a billion bytes)
