The CPU is considered the “Brain” of the computer.
It is responsible for the Fetch-Decode-Execute (FDE) cycle:
It Fetches instructions in its memory. Decodes it (works out what the instruction means). Then Executes the instructions (does the instruction).
How fast it does each cycle is called "Clock Speed".
The CPU can only do one instruction at a time, but it does it so fast that we think it is doing many things at once!
E.g. Watching a video and surfing the internet
It can do billions of instructions in a second.
