The order in which the instructions in a program are carried out. Normally the sequence proceeds in a linear fashion through the program, and the address of the instructions is obtained from the program counter in the control unit. This sequence is interrupted when a branch instruction is executed; at such a time the address field of the branch instruction is inserted into the program counter and the process continues. In the case of an indirect branch instruction, the memory content referred to by the address field of the instruction is inserted into the program counter.