in computer technology, a machine operation that contains no simpler operations denoted in the computer language. The execution of every computer instruction consists in the successive execution of some number of operations, including such elementary operations as resetting a register, resetting memory storage, shifting a character in a register left or right by one place, and transferring data between registers as well as the comparing of data items and logical addition and multiplication. The set of elementary operations must provide an algorithm for executing any system of computer instructions. Elementary operations may be combined into groups to provide a basis for microprogram control.