Linear Tape-Open (LTO) is a tape storage technology collaboratively developed by HP, IBM and Seagate Technology.
LTO-3 doubles the native capacity of the LTO-2 to 400 GB (800 GB compressed) and the transfer rate to 80 MB (160 MB) per second.
It was the first LTO generation to support the WORM feature.
Ultrium-3 provided backward compatibility for reading LTO-2 as well as LTO-1 cartridges.