The document describes the main components of a computer system unit. It contains electronic parts like the power supply, hard disk drive, CPU, fan, RAM, and motherboard. The front of the system unit has drive bays for inserting devices like DVD-ROM drives, CD-ROM drives, floppy disk drives, and more. Input/output ports on the back allow connection to peripherals. Key components include the power button, motherboard, power supply, disk drives, and hard disk drive which stores data and programs.

1. SYSTEM UNITPrepared by: masnizamustafa

2. SYSTEM UNITWhat is system unit?Box-like case that contains computer’s electronic components

3. SYSTEM UNITInside view of system unitCD-ROMPower supplyCasePowercablesHard disk driveCase fanCPU & fanFloopy driveInput/OutputData cablesRAMMotherboardBattery

4. SYSTEM UNITFront layer of a system unitDVD-ROM driveCD-ROM driveZip driveEmpty drive bayFloopy disk drivePower button/Reset button

5. SYSTEM UNITInput/Output port (I/O port)

6. SYSTEM UNITFunctions of the main components of a system unit1. Power button: To start on computer2. Motherboard: Main circuit board of the system unit, which has some electronic components3. Power Supply: Supplying power to the computer4. DVD-ROM drive: A device that reads DVD-ROM, also can read audio CDs, CDROMSs,CD-Rs and CD-RWs.5. CD-ROM drive: A device that reads audio CDs, CD-ROMs, CD-Rs and CD-RWs6. Floppy drive: A device that reads from and writes on a floppy disk7. Hard disk drive: Type of storage device that contains one or more inflexible, circular platters that store data, instructions and information.

7. exerciseLook at the diagram carefully and match them to the name of the ports in the table given using numbers.

8. exerciseMark T for True and F for False1. The processor (CPU) interprets and carries out the basic instructions that operate a computer. ( )2. Computers can use only one processor at a time. ( )3. ROM is the main circuit board of the system unit. ( )4. Expansion slot is a socket on the motherboard that can hold an adapter card.( )5. RAM is non-volatile. ( )6. The most important chip on the main circuit board is the microprocessorchip. ( )7. I/O port is the point at which a peripheral attaches to a system unit so that the peripheral can send data to or receive information from the computer. ( )8. Reset button is to start on computer. ( )9. A device that reads from and writes on a floppy disk is called hard disk drives. ( )10. Power supply convert standard electrical power into the form that computer can use. ( )