Part III-B: Computer Awareness

Fundamentals of Computers

A computer system comprises hardware (the physical components: CPU, memory, input/output devices) and software (the programs that run on the hardware, divided into system software such as operating systems, and application software such as word processors). The Central Processing Unit (CPU) is the "brain" of the computer, comprising the Arithmetic Logic Unit (ALU, which performs calculations), the Control Unit (which directs operations), and registers (small, fast storage locations).

Memory Hierarchy

Computer memory is organised in a hierarchy balancing speed and cost: registers (fastest, smallest, inside the CPU), cache memory (very fast, small, buffers between CPU and RAM), RAM or Random Access Memory (volatile, used for active programs and data), and secondary storage such as hard disk drives (HDDs) and solid-state drives (SSDs), which are non-volatile (retain data without power) but slower.

Operating Systems

An Operating System (OS) manages computer hardware and software resources and provides common services for programs. Common operating systems include Microsoft Windows, macOS, Linux, and Android. Key OS functions include process management, memory management, file system management, and providing a user interface (either command-line or graphical).

Networking Basics

A computer network connects two or more computers to share resources and information. Common network types include LAN (Local Area Network, confined to a small area like an office), WAN (Wide Area Network, spanning large geographic areas, of which the Internet is the largest example), and MAN (Metropolitan Area Network, spanning a city). The Internet operates using the TCP/IP protocol suite, and web pages are accessed via HTTP/HTTPS protocols using a browser.

Common Abbreviations

Frequently tested computer abbreviations include: CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read-Only Memory), URL (Uniform Resource Locator), HTML (HyperText Markup Language), USB (Universal Serial Bus), LAN (Local Area Network), WAN (Wide Area Network), PDF (Portable Document Format), and GUI (Graphical User Interface).

Practice Set — Computer Awareness (10 MCQs)

1. Which part of the computer is considered its "brain"?
   (a) CPU (b) RAM (c) Hard disk (d) Monitor
2. Which of the following is a volatile memory?
   (a) RAM (b) ROM (c) Hard disk (d) SSD
3. What does "LAN" stand for?
   (a) Local Area Network (b) Large Area Network (c) Long Access Network (d) Local Access Node
4. Which of the following is an operating system?
   (a) Windows (b) MS Word (c) Excel (d) Photoshop
5. What does "URL" stand for?
   (a) Uniform Resource Locator (b) Universal Reference Link (c) Uniform Reference Locator (d) Universal Resource Link
6. Which protocol is used to access secure web pages?
   (a) HTTPS (b) FTP (c) SMTP (d) TCP
7. Which of the following is non-volatile memory?
   (a) Hard disk (b) RAM (c) Cache (d) Registers
8. What does "GUI" stand for?
   (a) Graphical User Interface (b) General User Interface (c) Graphic Utility Instruction (d) Global User Input
9. Which unit of the CPU performs arithmetic calculations?
   (a) ALU (b) Control Unit (c) Cache (d) Register
10. Which of the following is the largest WAN in the world?
    (a) The Internet (b) A corporate intranet (c) A campus LAN (d) A home network

Answer Key

1.(a) The CPU is considered the computer's "brain," performing all processing tasks.

2.(a) RAM is volatile memory, losing its contents when power is removed.

3.(a) LAN stands for Local Area Network.

4.(a) Windows is an operating system; the others are application software.

5.(a) URL stands for Uniform Resource Locator.

6.(a) HTTPS is used to access secure web pages.

7.(a) A hard disk is non-volatile memory, retaining data without power.

8.(a) GUI stands for Graphical User Interface.

9.(a) The Arithmetic Logic Unit (ALU) performs arithmetic calculations.

10.(a) The Internet is the largest WAN in the world.