A computer program that is subsequently executed is called process. Process management is an operating system's way of dealing with running multiple processes on a single CPU. In a multitasking computer system, processes may occupy a variety of states. On the diagram above, we can see that there is no transition from the ready to waiting same with waiting to running. In
the ready state to waiting state, there is no transition between them
because you can only send the job in the waiting state if it came from
the running state. Also, it will proceed to the waiting state if there
are some interrupts and if it needs input/output request. In the
waiting state to running state, there is also no transition because the
process scheduler selects processes from the ready state for the CPU.
Also, all jobs in the waiting list was arranged and prepared to proceed
in the ready state. In addition, only the ready jobs or only the
jobs in the ready state will proceed to the running state to be run and
to bypass the ready state would make process management impossible.
There is no transition from the ready to waiting state is because in the ready state is ready in all aspects to make effective use of the CPU while in the waiting
state is waiting for peripheral device response which must be received
before the CPU can effectively be used again. If a job in the ready state cannot proceed because a required device fails, it should be sent back to the HOLD state, not the waiting state.
