Following are some causes why we use threads in designing operating systems.
A process with several threads makes a great server for instance printer server.
For the reason that threads can share common data, they do not require using inter process communication.
Because of the very nature, threads can take benefit of multiprocessors.
Threads are cheap in the logic that
They only require a stack and storage for registers therefore, threads are easy to create.
Threads use very small resources of an operating system in which they are working. That is, threads do not require new address space, global data, program code or operating system resources.
Context switching is fast when working with threads. The reason is that we only have to accumulate and/or restore PC, SP and registers.