DLT (digital linear tape) is a form of magnetic tape and drive system used for computer data storage and archiving. A special compression algorithm, known as Digital Lempel Ziv 1 (DLZ1), facilitates storage and retrieval of data at high speeds and in large quantities.
In the DLT drive, data is written on the tape in dozens of straight-line (linear) tracks, usually 128 or 208. Some cartridges can hold 70 gigabytes (GB) of data when compression is used. A variant of DLT technology, called SuperDLT, makes it possible to store upwards of 100 GB on a single cartridge. The SuperDLT drive can transfer data at speeds of up to 10 megabytes per second (MBps).
DLT is one of several technologies developed in recent years to increase the data-transfer rates and storage capacities of computer tape drives. Some examples of competing devices include the linear tape open (LTO) drive, the advanced intelligent tape (AIT) drive, and the Mammoth drive.