A hard real-time system guarantees that critical tasks complete on time. This goal requires that all delays in the system be bounded from the retrieval of the stored data to the time that it takes the operating system to finish any request made of it. A soft real time system where a critical real-time task gets priority over other tasks and retains that priority until it completes. As in hard real time systems kernel delays need to be bounded
A hard real time system guarntees that critical task be completed on time.Soft real time system where a critical real time task get priority over other tasks,and retain the priority untill it completes.