The document discusses the components of a computer system unit. It identifies the main components as the input/output ports, power button, reset button, motherboard, power supply, DVD-ROM drive, CD-ROM drive, DVD/CD-RW drive, zip drive, floppy drive, and hard disk drive. It explains that the input/output ports allow connection of peripheral devices, the power and reset buttons control power, and the drives and motherboard work together to read/write data and power the computer.

1. Computer Hardware
System Unit

2. Learning Outcome
• Student should be able to:
– Identify the component of a system unit
– State the functions of the main components of a
system unit.

3. Note Activity
Note 1 Activity 1
Note 2 Activity 2

4. Identify the components of a
system unit
• Inside view of system
unit
• Front layer of a
system unit
• Input / output port ( I/O port)

5. Inside view of system unit

6. Front layer of a system unit

7. Input / output port ( I/O port)

8. Function of the main components
of a system unit
Components Functions
Input / output port Peripheral can send data to or receive
information from the computer.
An external device, such as a keyboard,
monitor, printer, mouse and microphone
is often attached by a cable to a port on
the system unit.
Power button To start on computer
Reset button Kick of soft boot, instructing the
computer to go through the process of
shutting down, which would clear
memory and reset devices to their
initialized state. It simply removes power
immediately.

9. Motherboard Main circuit board of the system unit.
Which has some electronic components
attached to it and other built into it
Power supply Convert standard electrical power into the
form that computer can use. If a power
supply is not providing the necessary
power, the computer will not function
properly.
DVD-ROM drive A device that reads DVD-ROM , also can
read audio CDs, CD-ROMs, CD-Rs and CD-
RWs
CD-ROM drive A device that reads audio CDs, CD-ROMs,
CD-Rs and CD-RWs.
DVD/CD-RW drive It is a combination drive that reads DVD
and CD media. It is also writes to CD-RW
media. This drive also allows watching a
DVD or burn a CD.
Zip drive A high capacity disk drive that reads from
and writes on a Zip disk.

10. Floppy drive A device that reads from and writes on a
floppy disk
Hard disk drive Type of storage device that contains one
or more inflexible =, circular platters that
store data, instructions and information.
Also called a hard disk.