3. Arithmetic Logic Unit

CPUs have several components, each performs a specific role. Together, they are responsible for processing all of the program instructions given to the CPU.

The first of these components is the Arithmetic Logic Unit, or ALU.

The ALU is the part of the CPU that carries out all of the calculations. This includes both arithmetic operations (adding, subtracting, multiplying, etc) and logic operations (such as comparison)

The result of the ALUs calculations is stored in memory. This memory is usually a very fast kind of memory called a 'register', located as close to the ALU as possible inside the CPU.