Basic Computer Hardware Components – JSS1 Computer Hardware & GSM Repair Lesson Note (First Term)

Computer hardware is the physical parts of a computer that you can see and touch.

Behavioural objectives

1. Define computer hardware.
2. Name the four groups of hardware: input, processing, output and storage.
3. Give at least two examples of each group.
4. State the job of the CPU.
5. Describe how the groups work together when a letter is typed and printed.

What is computer hardware?

Hardware is every physical part of a computer that can be touched.

• Hardware: the parts you can touch, such as the keyboard, monitor and mouse.
• Software: the programmes and instructions that tell the hardware what to do, such as Microsoft Word.

What are the groups of computer hardware?

There are four main groups of hardware: input devices, the processing device, output devices and storage devices.

What are input devices?

Input devices are the parts we use to send information into the computer.

They are how we tell the computer what to do. Without them, the computer would just sit and wait.

• Keyboard: used for typing letters and numbers.
• Mouse: a pointing device used to click on icons.
• Microphone: used to “input” your voice or sounds.
• Scanner: copies a paper document or photo into the computer.
• Webcam: captures live pictures and video for the computer.

What is the processing device?

The processing device is the CPU (Central Processing Unit), the part that works on information and follows instructions.

• CPU: the “Brain” of the computer. It is a tiny chip inside the system unit.
• Its job: it follows your instructions. If you click “Print”, the CPU tells the printer to start working.
• System unit: the box that holds the CPU and other main parts inside the computer.

What are output devices?

Output devices are the parts that show or tell us the result of the computer’s work.

After the CPU finishes “thinking”, it sends the result to an output device.

• Monitor (screen): shows pictures, videos and the words we type.
• Printer: puts information from the screen onto paper.
• Speakers: let us hear sounds and music.
• Headphones: let one person hear sound privately through the ears.
• Projector: shows the screen picture on a wall or large screen for a class.

What are storage devices?

Storage devices are the parts that keep information safely so it can be used again later.

They act like a cupboard or filing cabinet where the computer keeps your work.

• Hard Disk Drive (HDD): found inside the computer. It holds almost everything: games, photos and the computer’s own software.
• Solid State Drive (SSD): an internal drive with no moving parts. It is usually faster than an HDD.
• USB flash drive: a small portable drive you carry in your pocket to move files between computers.
• Memory card: often used in phones and cameras to save pictures.

What is the difference between storage and RAM?

Storage keeps files even when the computer is off. RAM (Random Access Memory) holds work temporarily while the computer is on.

How do the hardware groups work together?

The groups work as a chain: input, processing, storage and output.

Imagine you are writing a letter to a friend:

1. Input: you use the keyboard to type the words.
2. Processing: the CPU organises the letters so they make sense.
3. Storage: you save the letter on your flash drive.
4. Output: you use the printer to get the letter on paper.

How should we take care of computer hardware?

• Keep it clean: wipe away dust gently with a dry soft cloth.
• Keep liquids away: water and drinks can damage the keyboard and other parts.
• Shut down properly: use the Shut down option before switching off the power.
• Handle gently: do not force plugs or flash drives into a port.

Evaluation

1. Mention two input devices you see in the computer lab.
2. Why is the CPU called the “Brain” of the computer?
3. If you want to listen to music without disturbing others, which output device should you use? (Hint: it goes on your ears.)
4. Name two storage devices and say where each is used.

Assignment

1. Draw a table with four columns: Input, Processing, Output and Storage.
2. Write at least two devices under each column, except Processing, which needs only the CPU.