DEFINITIONS OF BASIC COMPUTER COMPONENTS

To start with, I will like to describe basic parts of the computer system

MOTHERBOARD:     The main board of computer; the central processor unit (CPU) is on the     motherboard; all adapter cards are plug into the motherboard; it is the largest single board in computer. There are several types of CPU chips found on motherboards

POWER SUPPLY:            Provides electrical power to motherboard, disk drives, and occasionally to the monitor also. It has a fan on it to cool the computer.

VIDEO CARD:           Adapter card that sends video signals to the monitor; 4 main kinds of video cards:

Hercules: Monochrome & high-res graphics (now obsolete)

CGA: Color & low-res graphics (now obsolete)

EGA: More colors and high-res graphics (now obsolete)

VGA: Lots of colors and very-high-res graphics

(VGA and Super VGA are compatible)

HARD DISK:          Stores large quantities of data for use at a later time. Uses a HARD DISK CONTROLLER to connect hard disk to motherboard.

MFM and RLL drives: Typically have separate controllers and hard disks. RLL controllers can store up to 30% more data on the same disk than MFM controllers. Uses 34-pin AND 20-pin cables to transmit data.

IDE Drives: Have hard disk controller and hard disk in ONE unit; slightly more difficult to install additional hard disks to IDE systems. Uses 40-pin ribbon cable to transmit data.

SCSI drives: Uses separate controllers, like MFM & RLL drives, but can transfer data at a much faster rate. SCSI drives are also more expensive. Uses 50-pin or 68-pin cable to transmit data.

FLOPPY DISK DRIVE:   Stores smaller quantities of data than a hard disk. Uses a FLOPPY DISK ONTROLLER to connect drive to motherboard. 4 main floppy drive types:

5 1/4" 360K: Stores 362,496 bytes of data (double density)

5 1/4" 1.2M: Stores 1,213,952 bytes of data (high density)

3 1/2" 720K: Stores 720,112 bytes of data (double density)

3 1/2" 1.4M: Stores 1,457,664 bytes of data (high density)

PARALLEL PORT:           Connects printer to computer; sends 8 bits of data (1 byte) at a time.

SERIAL PORT:                Connects serial devices (mouse, modem, plotter, digitizer) to computer; sends 1 bit of data at a time.

RAM:                            Random Access Memory; this is the workspace or desktop of your computer.

EMS CARD:                  Expanded Memory card; adds extra RAM memory to computers that have no more expansion capacity on the motherboard.

NETWORK INTERFACE:  Connects your computer to a network of other card 

MS-DOS (OR PC-DOS): The Disk Operating System; controls all of the disk drives as related to the   computer.

APPLICATIONS:            Any programs you use in the DOS environment (Lotus, WordPerfect, etc.)

NETWORK OPERATING SYSTEM:            Like DOS, but allows the computer and you to use  software on the network hard drives.

CD-ROM DRIVE:           Reads data from Compact Discs (CDs); up to 688MB of data can be stored on 1 CD; READ-ONLY technology - generally, you can't write to a Compact Disc.

SOUND CARD:              Provides stereo sound from your PC, through EXTERNAL speakers.