What is a computer?
📖 In short
A computer is a clever machine that helps us write, draw, calculate, play and talk to people everywhere. But it doesn't really think on its own: it follows instructions written by people, very, very fast. Today we find computers everywhere: on desks, in phones, in cars and even in washing machines!
🤩 Did you know?
- The word “computer” comes from “compute”, meaning to calculate, because the first computers were built to do sums.
- A modern car has dozens of small computers: for the engine, the brakes, the radio and the air conditioning.
- The phone in your pocket is more powerful than the computer that helped astronauts reach the Moon in 1969.
- Some supercomputers do more than a billion billion calculations in a single second!
🔎 Find out more
🌟 Computers come in many shapes
When we hear the word “computer”, we picture a screen and a keyboard. But a smartphone is a computer, a tablet is a computer, there's one in a games console and a tiny one in a smartwatch. They all take in information, process it and give us a result.
🔍 The parts we can see
The screen shows pictures and words, we type with the keyboard, and we move the pointer and click with the mouse. These parts we can touch and see are called “hardware”.
💡 The programs we can't touch
Games, the web browser and the drawing program are “software”: written instructions that tell the computer what to do. Hardware without software is like a notebook with no words, and software without hardware is like a story with no book.
🎯 Why do we need it?
Computers help doctors see inside the body, pilots fly planes, scientists study the weather and pupils look things up. A computer is a wonderful tool if we know how to use it well.
🧭 The computer follows instructions
A computer is very fast, but it only understands what we explain to it exactly. If we tell it “draw something pretty”, it won't know what to do, but “draw a yellow circle at the top of the page” it does straight away.
🌈 Computers we can't see
In a washing machine, a little computer chooses how long to wash; in a traffic light, a computer changes the colors; and in a plane, many computers help the pilot. These are called “embedded computers” because they are hidden inside machines.
📊 See how it works
📚 Key words
- Hardware
- The parts of a computer we can touch and see
- Software
- The programs and instructions that tell the computer what to do
- Embedded computer
- A small computer hidden inside another machine
🧪 Try it at home
Look around your home for machines with a little computer inside: do they have a screen, buttons or lights that change? Make a list, and you'll be surprised how long it is!
🧩 Test yourself
1 What do we call the instructions that tell a computer what to do?
2 Which of these also has a computer inside?