Real-time computing
Soft real-time systems: On average, these systems work fast enough to make it feel like real-time. A videoconferencing system has microseconds to record sound and video, to send them to the other party, and to process the incoming data. If at one time, this cannot be done, the video will be blurred, and the sound may be out of sync for a few moments. This is however not a catastrophe, and the system can continue to work.