The Fetch-Execute Cycle
A Fetch-Execute Cycle is the basic operational process of a computer. It is the process by which a computer retrieves a program instruction from its memory, determines what actions the instruction dictates, and carries out those actions. This cycle is repeated continuously by a computer's Central Processing Unit (CPU), from boot-up to when the computer is shut down.
In the fetch-execute cycle, the instruction is fetched from the memory adress currently stored in the Program Counter (PC) and is then stored in the Current Instruction Register (CIR). The PC is then incremented (increased by 1) so that the next instruction can be processed.