The picture above shows the inside of a microprocessor at work. The microprocessor, (also called the central processing unit), is the brain of the computer. The central processing unit, (or CPU), with its level 1 cache memory, contains the control unit and the arithmetic/logic unit, both working together as a team to process the computer's commands. The control unit fetches instructions from memory and decodes them into commands that the computer can understand. The arithmetic/logic unit takes these commands and executes them, storing the results back into memory. These 4 steps, (fetch, decode, execute, and store), are what's called the "machine cycle" of a computer. Newer computers can complete over 3 billion of these each and every second! The CPU's level 1 cache memory is located inside of the CPU. Level 2 cache memory is further away and slower than level 1 cache memory. The CPU can use the cache memory much faster than having to use the other memory. The clock driver is also inside of the CPU. It is what sets the pace for the computer. Below is a top and bottom picture of a CPU. Below that is another picture of a CPU with its fan and heatsink. The CPU needs a fan and heatsink to keep from getting too hot.
