Types and Components of Computer Systems

Hardware & Software

Hardware

• The electronic, physical components of a computer system, including input and output devices.
  • Internal Hardware Devices:
    • Central Processing Unit (CPU)
    • Processor
    • Motherboard
    • Internal memory (RAM & ROM)
    • Graphics & Sound Cards
    • Internal Storage (HDDs & SSDs)
    • Network Interface Card (NIC)
  • External Hardware Devices:
    • Monitor
    • Keyboard
    • Mouse
    • Printer
    • External Storage Devices

Software

• Techniques, methods, commands, and instructions for controlling a computer system and processing data.
• Two types of software:
  • Application Software:
    • Services for specific tasks (e.g., spreadsheets, databases, word processors).
  • System Software:
    • Provides a platform for applications to run.
    • Includes compilers, linkers, device drivers, utilities, and operating systems (OS).

Analogue and Digital Data

• Computers process data in binary form (0, 1) known as digital data.
• Real-world data is analogue.
• Conversion:
  • ADC (Analogue to Digital Converter) converts analogue to digital.
  • DAC (Digital to Analogue Converter) outputs data back in analogue form.

The Main Components of Computer Systems

Central Processing Unit (CPU)

• Executes hardware and software operations, known as microprocessor.
• Comprises:
  • Control Unit (CU)
  • Arithmetic Logic Unit (ALU)
  • Registers

Internal Memory

1. RAM:
   • Temporary storage, volatile.
   • Used for current data/processes.
2. ROM:
   • Permanent storage, non-volatile.
   • Stores configuration data (e.g., BIOS).

Input & Output Devices

Backing and Secondary Storage

• Permanent data storage.
• Typically HDDs and SSDs.

Differentiation:

1. RAM is temporary; backing storage is permanent.
2. RAM and ROM are smaller than backing storage.
3. Faster access with RAM and ROM.

Operating Systems

• Control operations of input/output & storage.
• Manage application loading/running/storage.
• Handle application errors and maintain security/logs.

Types of User Interfaces

1. Command Line Interface (CLI):
   • Requires typing commands; used by programmers.
2. Graphical User Interface (GUI):
   • User-friendly with icons; used by end-users.
3. Dialogue-based Interface:
   • Voice commands; useful for disabled users.
4. Gesture-based Interface:
   • Human interaction through movement; intuitive but limited.

Types of Computers

Desktop Computers

• General-purpose, separate components.
• Advantages:
  • Easier upgrades, standardized parts, better specs, stable connections.
• Disadvantages:
  • Not portable, cluttered workspace.

Mobile Computers

1. Laptop Computers:
   • All-in-one design; portable.
   • Advantages:
     • High portability, less desk clutter.
   • Disadvantages:
     • Theft risk, limited battery life.
2. Smartphones:
   • Phone calls and apps; highly portable.
   • Advantages:
     • Small, internet access on the go.
   • Disadvantages:
     • Difficult typing, limited memory.
3. Tablets:
   • Larger than smartphones, touch screen.
   • Advantages:
     • Fast startup, simple to use.
   • Disadvantages:
     • Expensive, limited storage.
4. Phablets:
   • Hybrid of tablets and smartphones.

Impact of Emerging Technologies

• Artificial Intelligence (AI):
  • Machines performing intelligent tasks.
  • Everyday applications: autonomous vehicles, robotic assistance.
  • Negative impacts:
    • Unemployment, dependency on tech, de-skilling.
• Extended Reality (XR):
  • Merges real and virtual environments.
  • Examples:
    • Augmented Reality (AR): Merges virtual with physical.
    • Virtual Reality (VR): Immersive environments for training, education.