ICT 0417 - 1 Types and Components of Computer Systems

This section introduces the fundamental hardware components of a computer system. Understanding these components is crucial for comprehending how a computer functions.

1.1 Types of Computer Systems

Computers can be classified based on their size, processing power, and intended use. The main types are:

• Microcomputers: Designed for individual use. Examples include desktops, laptops, and tablets.
• Mainframe Computers: Powerful systems used by large organizations for processing vast amounts of data.
• Supercomputers: The most powerful type of computer, used for complex calculations and simulations.
• Embedded Systems: Specialized computers embedded within other devices, such as washing machines, cars, and medical equipment.

1.2 Key Hardware Components

The core hardware components of a typical microcomputer system are:

1.2.1 Central Processing Unit (CPU)

The 'brain' of the computer. It fetches instructions, decodes them, and executes them. It performs arithmetic, logical, control, and input/output operations.

Feature	Description
Clock Speed	Measured in GHz (gigahertz), indicates how many instructions the CPU can process per second. Higher clock speed generally means faster processing.
Cores	Multiple processing units within a single CPU. More cores allow the CPU to handle multiple tasks simultaneously.
Cache Memory	Small, fast memory within the CPU used to store frequently accessed data.

1.2.2 Memory (RAM)

Random Access Memory (RAM) is the computer's short-term memory. It stores data and instructions that the CPU is actively using. Data in RAM is lost when the power is turned off.

Types of RAM:

• DRAM (Dynamic RAM): Requires periodic refreshing to retain data.
• SRAM (Static RAM): Faster and more expensive than DRAM; does not require refreshing.

1.2.3 Storage Devices

Used for long-term storage of data, programs, and the operating system.

• Hard Disk Drive (HDD): Uses magnetic platters to store data. Relatively inexpensive but slower than SSDs.
• Solid State Drive (SSD): Uses flash memory to store data. Faster, more durable, and more expensive than HDDs.
• USB Flash Drives: Portable storage devices using flash memory.
• Optical Drives (CD/DVD/Blu-ray): Use lasers to read and write data to optical discs.

1.2.4 Motherboard

The main circuit board of the computer. It connects all the other components together and provides pathways for communication between them.

1.2.5 Graphics Processing Unit (GPU)

Dedicated to processing graphics and video. Important for gaming, video editing, and other visually intensive tasks. Can be integrated into the CPU or a separate card.

1.2.6 Power Supply Unit (PSU)

Converts AC power from the wall outlet into DC power that the computer components can use.

1.2.7 Input Devices

Allow users to enter data and instructions into the computer.

• Keyboard: Used for typing text and commands.
• Mouse: Used for pointing and selecting items on the screen.
• Microphone: Used for recording audio.
• Scanner: Used for converting physical documents into digital images.

1.2.8 Output Devices

Display or present information from the computer to the user.

• Monitor: Displays visual output.
• Printer: Produces hard copies of documents.
• Speakers: Produce audio output.

1.3 Diagram of a Computer System

1.4 Input and Output (I/O) Ports

Ports on the computer allow connection to external devices.

• USB Ports: Versatile ports for connecting a wide range of devices.
• HDMI Ports: For connecting displays and other video devices.
• Ethernet Ports: For connecting to a network.
• Audio Ports: For connecting headphones and speakers.