Real-time computing
Hard real-time systems: After the delay has passed the result is totally useless (and considered to be an error). No matter what happens, hard-real time systems deliver the result in the specified time. Real world examples are the controller for the airbag in a car. The reaction time of an airbag system is around 1 ms. Another example for a hard real-time system is the Anti-lock braking system in a car. If it does not react fast enough, an accident will occur. People might die because the result was not there fast enough.