<P> A computer program is a collection of instructions for performing a specific task that is designed to solve a specific class of problems . The instructions of a program are designed to be executed by a computer and it is required that a computer is able to execute programs in order for it to function . </P> <P> The instructions of a computer program are often specified by a computer programmer . A computer programmer does this by means of the application of a programming language . From the program in its human - readable form of source code, a compiler can derive machine code, which are computer program instructions that--as a result of being specified in a language that a computer can understand--are able to be directly executed by the computer they have been provided to . Alternatively, a computer program may be executed with the aid of an interpreter . </P>

A set of instructions that the computer will follow is called a