Time Sharing
In time sharing, it is possible for multiple users to run more than one application at the same time on the computer. This is accomplished by providing a=separate terminal to each user. All these terminals are connected to the main computer. The GPU time is divided among all the users on a scheduled basis. The time that each user gets is called a time slice. The CPU switches from one user to the another, and e|^cutes a part of the process in the time slice. This process continues till the job is executed. In time sharing, like in multiprogramming only one program is in control of the CPU at any given time.
In time sharing environment, it is not always possible that all the programs of all the users reside in the main memory. Only the control program and some programs reside in the main memory. The remaining programs are loaded from the secondary memory as and when they are to be executed.