Digital audio tape

Digital Audio Tape (DAT or R-DAT) is a signal recording and playback medium developed by Sony in the mid 1980s. In appearance it is similar to a compact audio cassette, using 4 mm magnetic tape enclosed in a protective shell, but is roughly half the size at 73 mm × 54 mm × 10.5 mm. As the name suggests, the recording is digital rather than analog. DAT has the ability to record at higher, equal or lower sampling rates than a CD (48, 44.1 or 32 kHz sampling rate respectively) at 16 bits quantization. If a digital source is copied then the DAT will produce an exact clone, unlike other digital media such as Digital Compact Cassette or non-Hi-MD MiniDisc, both of which use lossy data compression.

Like most formats of videocassette, a DAT cassette may only be recorded on one side, unlike an analog compact audio cassette.