What is a computer?

Computers are everywhere. You probably have over a hundred computers at home. No kidding! They are hidden in everything from cellphones to cars to coffee machines. Can you count how many computers you’ve seen today?

Spot the computer!

Computers are machines that do stuff with data with instructions. Computers are built with hardware and software. They are both needed. The electrical or mechanical parts of a computer are called hardware. The instructions and the programs that run inside the computer are the software.

The tiny computers that live inside your every day stuff are called microcontrollers. Instead of having screens and keyboards and hard drives everything fits into one tiny circuit. Microcontrollers still have a processor, memory and different input/output systems.

Imagine if everything had a computer inside and you'd have the universal remote. In the future more and more things will be programmable!


  • Can a car be a computer?
  • What about a dog?
  • Can a toilet be a computer?
  • What about a grocery store aisle?

You might think none of these are computers. But cars already have many computers - like the navigation system. Grocery stores have cash registers. Even toilets have computers (at least in Japan!). Computers are getting smaller and cheaper all the time. In the future dogs will probably have computers in their collarbones and so will every milk bottle. Can you imagine what kind of computers there might be in the future? Can you draw a few?

Make more computers

Some microcontrollers have sensors that monitor the changes in the environment. Can you design a computer around the following sensors?

  • Temperature. When the temperature gets hot, do this:
  • Orientation. When the door is left open, do this:
  • Vibration. When someone knocks on the door, do this:
  • Moisture. When it rains do this:
  • Internet. When there's a new toy in sale, do this:

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