Multiprogramming operating system

In the multiprogramming system, the user can store more than one process in the main memory. The process can have 3 phases:
1. Input
2. Execution phase
3. Output phase
In this, the process execute simultaneously. Consider 2 process p1 and p2. In the First interval time, the process P1 uses CPU. In the second interval time, it uses input/output device. So, second process can have the CPU in the second interval time. This multiprogramming increases the resource utilization by exploiting the concurrence between the CPU and the Input Output sub system. In multiprogramming system CPU switched between the process frequently.