The purpose of multiprogramming is to increase the utilization of the computer system as a whole. More than one program is loaded into the memory of a computer. Generally it is used in multi-user environment. CPU can execute only one instruction at a time; it cannot simultaneously execute instructions from two or more programs. However, it can execute instructions from one program then from second program then from first again and so on. This type of processing is referred to as â€œconcurrent executionâ€ though it is not concurrent execution and also called as Multiprogramming.