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2. Parts of a CPU

The Central Processing Unit (CPU) is a hugely complicated electronic chip consisting of billions of individual transistors.

There is a logical arrangement of functions within the chip. With each part having a specific role to perform.

The major parts are

  • The Control Unit (CU)
  • The Arithmetic Logic Unit (ALU)
  • The Registers.

The diagram below shows the arrangement of these components within the CPU:

CPU and Motherboard


There are three main buses connecting all the parts together. These are the Data Bus, which carries the data, the Address Bus which carries information on the location of the data and the Control Bus, which handles commands to other devices such as the hard disk, the monitor and the graphics card.

Challenge See if you can find out one extra fact on this topic that we haven't already told you

Click on this link: Parts of a CPU