What Are DAT Tapes And What Are They Used For?
DAT stands for Digital Audio Tape and was a popular tape based storage medium in the late 1980s. Developed by Sony these new tapes (often referred to as cartridges) looked a lot like the normal audio tapes but were different on the inside (they were based on digital rather than analogue technology) and were also physically far smaller. DAT was originally designed for audio only work but because of the digital format it was quite easily adapted as a computer backup device. DAT offered anywhere from 1.3GB ot 72GB of storage space and the computer variant of DAT was known as DDS (Digital Data Storage) - this storage method is still somewhat popular but it's days are strictly limited.
Despite it's high speed and digital format DAT still suffers from the same problem as all tape drives - you can only ever access data sequentially which means compared to pretty much any other mass storage device it's still slow, the tapes can snap or get tangled and the tapes/cartridges have a very limited lifespan due to oxidation and other factors.