the difference between the Hard and Soft real time system can be defined by the bearable output latency of the Job that the system is doing. In case of a hard real time system any latency in the output is not tolerated or any delay in the output is equivalent to no output by the system.
in case of a Soft real time system the latency is accepted.

Example of
Hard real time system: Communication systems in Aircraft, Critical Medical equipments
Soft real time system : like Projectors, TV etc