Features of a Computer – JSS1 Computer Studies Lesson Note (Second Term)

A computer is an electronic machine that can take in information (input), process it, store it, and give out information (output). It follows instructions given by people and can do many tasks very quickly. Computers come in different shapes and sizes, from big machines to small phones that fit in your pocket.

Behavioural objectives

By the end of the lesson, students should be able to:

• State the meaning of a computer.
• List the main features of a computer.
• Explain speed, accuracy, storage capacity, diligence, versatility and reliability, with examples.
• State the difference between short-term memory (RAM) and long-term memory (storage).
• Describe what the CPU does.
• Name the types of storage, connection and user interface found on modern computers.

What are the main features of a computer?

1. Speed

Computers work very fast. They can do millions or billions of calculations in just one second. This means:

• They can solve hard maths problems quickly
• They can search through lots of information in moments
• They can run many programs at the same time
• They can play games with moving pictures smoothly
• They can process big files like videos without waiting long

The speed of a computer is measured in hertz (Hz). Modern computers work at gigahertz speed, which means billions of operations per second.

2. Accuracy

Computers are very accurate. They don’t make mistakes in their calculations if they have the right instructions. This means:

• The answers they give to maths problems are correct
• They don’t forget steps when following instructions
• They don’t get tired and start making mistakes
• They can keep track of tiny details
• They give the same answer every time with the same input

However, computers can only be as accurate as the instructions and information given to them by people. If a person makes a mistake when giving instructions, the computer will follow those wrong instructions perfectly.

3. Storage capacity

Computers can store huge amounts of information. They can keep:

• Thousands of books
• Hundreds of movies
• Millions of pictures
• Years of music
• Billions of numbers and facts

Storage is measured in bytes. Modern computers have:

• Gigabytes (billions of bytes)
• Terabytes (trillions of bytes)

Storage can be:

• Internal (inside the computer)
• External (connected to the computer, like USB drives)
• Cloud storage (kept on the internet)

4. Diligence (never gets tired)

Unlike humans, computers never get tired. They can:

• Work 24 hours a day, 7 days a week
• Do the same task over and over without complaining
• Keep the same speed and accuracy all day and night
• Run for years without needing a break
• Work in dangerous places where humans can’t go

This makes computers perfect for boring or repetitive jobs that would make people tired or unhappy.

5. Versatility (can do many different things)

Computers can do many different kinds of jobs. The same computer can:

• Write letters and documents
• Play music and videos
• Connect to the internet
• Make calculations
• Play games
• Draw pictures
• Edit photos and videos
• Control other machines
• Talk to other computers

You just need to give the computer different instructions (programs) for each job.

6. Reliability

Computers are reliable, which means they work the same way every time. When you:

• Press the same button, you get the same result
• Give the same input, you get the same output
• Save a file, you can find it again later
• Follow the same steps, you get the same outcome

This makes computers dependable for important tasks.

7. No feelings

Computers don’t have feelings or opinions. This means they:

• Don’t get bored with repetitive tasks
• Don’t play favourites with different users
• Don’t have bad days when they work poorly
• Don’t get excited and make mistakes
• Don’t hold grudges or remember past errors

This can be good for tasks that need to be fair and unbiased.

8. Memory

Computers have two main types of memory.

Short-term memory (RAM)

• Stands for Random Access Memory
• Holds information the computer is currently using
• Is very fast to access
• Gets emptied when the computer turns off
• Helps the computer work on many things at once

Long-term memory (storage)

• Keeps information even when the computer is off
• Can hold much more information than RAM
• Is slower to access than RAM
• Includes hard drives, SSDs, and other storage devices
• Stores your files, programs, and the operating system

9. Automation

Computers can do tasks automatically without needing a person to control every step. They can:

• Send emails at certain times
• Update programs when needed
• Back up files without being asked
• Monitor systems and report problems
• Follow a set of instructions on their own

This saves time and helps prevent human error.

10. Processing power

The brain of the computer is called the CPU (Central Processing Unit). It:

• Controls all the operations of the computer
• Does all the calculations and thinking
• Follows the instructions in computer programs
• Manages the flow of information
• Makes decisions based on the data it receives

More powerful CPUs can handle more complex tasks and work faster.

What are the additional features of modern computers?

11. Connectivity

Modern computers can connect to other computers and devices:

• Through the internet
• Using cables
• Using wireless connections like WiFi and Bluetooth
• Through networks in offices or schools
• To printers, speakers, and other devices

This connectivity helps share information and work together.

12. Multimedia

Computers can work with many types of media:

• Text
• Pictures
• Sound
• Video
• Animation
• 3D models

This makes computers good for entertainment and creative work.

13. User interface

The way people interact with computers is called the user interface. It can be:

• Graphical (with pictures, buttons, and windows)
• Command-based (typing instructions)
• Touch screen (touching the screen directly)
• Voice-controlled (talking to the computer)
• Virtual reality (using special headsets)

Good interfaces make computers easier to use.

Evaluation

1. What is a computer?
2. List five features of a computer.
3. Why is a computer only as accurate as the instructions given to it?
4. State two differences between RAM and long-term memory.
5. What is the CPU, and what does it do?

Assignment

1. Choose any four features of a computer and explain each in one or two sentences.
2. Name the three kinds of storage and give one example of each.
3. List four types of user interface.