Program counter

The program counter (in English Program Counter or PC), also called event counter (The Instruction Pointer), part of the central processing unit in some computers, is a register of a computer's processor that indicates the position of the processor in its sequence of instructions.. Depending on the details of the particular machine, it contains either the address of the instruction being executed, or the address of the next instruction to be executed. The program counter is automatically incremented at each instruction cycle so that the instructions are read in sequence from memory. Certain instructions, such as branches and subroutine calls and returns, break the sequence by placing a new value in the program counter.