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1. What is the CPU?

The CPU is often described as the 'brain' of the computer (although that isn't a technical term so don't write it in an exam). The CPU is an electronic chip called a microprocessor.

The CPU fetches instructions from main memory (RAM), it decodes them and then executes them. The instructions are provided by a computer program.

The purpose of the CPU is to process data. It is where all the searching, sorting, calculating and decision making takes place within the computer.

So no matter what you do on your computer, whether it be writing an essay, looking at your photographs or checking your emails, the CPU has dealt with all of the data and processing required to make these tasks possible.

Another task performed by the CPU is to control all the other component parts of the computer for example:

  • Hard disk
  • DVD drive
  • Sound system
  • Graphics system

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