Storage device for stream data such as digital video and for non-stream data such as computer files, comprising a single file system which features a first type of storage unit for storing audio and/or video streams and a second type of storage unit for storing non-stream data, wherein the size of the first storage unit is a multiple of the size of the second storage unit, said device further comprising means for allocating a unit of the first type either for stream storage or to split a unit of the first type into a plurality of units of the second type, for storage of non-stream data. The invention also concerns a method for storing stream data or non-stream data. Applicable in digital television systems.