Linear Tape-Open
LTO tapes are read and written to with a tape drive. This is typically connected to a computer using serial attached SCSI, although some tape drives use Fibre Channel. LTO drives are very expensive, but the tapes are much cheaper than an equivalent-sized hard drive or optical disc. Unlike many other tape formats, LTO cartridges contain only a single reel of tape. The other reel is inside the drive. This means that the tape must be rewound before it can be removed from the drive. This makes the cartridge smaller because it does not need to contain an empty reel. It also makes the drives more expensive because they must contain a mechanically complex mechanism to pull the tape out of the cartridge and thread it onto the takeup reel. Unlike most other tape drives, LTO drives do not have a rotating head drum, and do not use helical scan. The head writes tracks in a straight line, like a reel-to-reel audio recorder. This is where the name comes from. The head can, however, move up and down to write multiple tracks to the tape. This is similar to the way an 8 track tape works, although since the head is much smaller, an LTO tape can have hundreds or thousands of tracks (up to 8960 tracks for LTO-9). This allows many terabytes of data (up to 18 TB for LTO-9) to be stored on a single tape.