realtime means your algorithm is guaranteed within a certain window of time, even accounting for delays talking to memory, caches, etc. If it's okay to "drop fr

realtime means your algorithm is guaranteed within a certain window of time, even accounting for delays talking to memory, caches, etc. If it's okay to "drop frames" it is referred to as "soft real time", otherwise it is referred to as "hard real time". Soft example: Video decoding. Hard example: Mars rover.