A five-state process model
Five states: New, Ready, Running, Blocked, Exit
New : A process has been created but has not yet been admitted to the pool of executable processes.
Ready : Processes that are prepared to run if given an opportunity. That is, they are not waiting on anything except the CPU availability.
Running: The process that is currently being executed. (Assume single processor for simplicity.)
Blocked : A process that cannot execute until a specified event such as an IO completion occurs.
Exit: A process that has been released by OS either after normal termination or after abnormal termination (error).