The document discusses the key components that make up a personal computer's system unit, including the motherboard, central processing unit, memory, drives, power supply, and adapter cards located inside the metal or plastic casing. The motherboard holds the central processing unit and memory chips, and connects the computer's main components. Random access memory temporarily stores data and information for quick access by the central processing unit, while read-only memory permanently stores basic startup instructions for the computer.

1. KNOWING A PERSONAL COMPUTER (PC) SYSTEM UNIT

2. System Unit is a metal or plastic casing box SYSTEM UNIT

3. A System Unit consists of a : Motherboard Drives A Power Supply Memory Card Adapter Card SYSTEM UNIT

4. In front of a system unit, we can see the following parts: SYSTEM UNIT

5. Inside a system unit, we can see the following parts: SYSTEM UNIT

6. Motherboard is a main electronic board. It holds a Central Processing Unit, Memory and Adapter Cards. Motherboard

7. Central Processing Unit (CPU) A CPU is an electronic chip. It is the ‘brain’ or ‘heart’ of a PC. It processes data and information.

8. Computer Memory A computer memory is a small data storage device. Computer memory has two type : Random Access Memory (RAM) Read Only Memory (ROM)

9. Random Access Memory (RAM) It holds information / data temporarily that we might need to access quickly.

10. Read Only Memory (ROM) It stores data permanently.