My question is regarding time-sharing and multi-tasking systems.

Time-sharing operating system assigns time slot to each task while multi-tasking OS runs various jobs in parallel.

But as I get it, on a single processor system, time-sharing is the only way to achieve multi-tasking. (I don't know if I am correct on this premise.)

So, are time-sharing and multi-tasking system same or different.
And if they are different, then what are the key differences (particularly on a single-processor/single-core system with no hyper-threading support etc) ?


  • $\begingroup$ They are same. The term time-sharing operating system is now obsolete and now only the term Multi-tasking operating system is used. $\endgroup$
    – vikram
    Aug 20, 2014 at 9:07

1 Answer 1


Just as multiprogramming allows the processor to handle multiple batch jobs at a time, multiprogramming can also be used to handle multiple interactive jobs. In this latter case, the technique is reffered to as time sharing, because processor time is shared among multiple users. In a time-sharing system, multiple users simultaneously access the system through terminals, with the OS interleaving the execution of each user program in a short burst or quantum of computation.

William Stallings, Operating Systems Internals and Design Principles, 7th Edition

You should keep in mind that the principal objective of a time sharing system is not to maximize processor use, but to minimize response time.

I think it would be correct however to assert that on a single processor system, multi-tasking is achieved through time sharing. Remember that a processor can execute only one task at a time at any given time.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.