Zip was a high-capacity floppy disk format originally introduced in 1995 by Iomega. Initially, it had a capacity of 100 MB, later increased to 250 MB in 2001, and again to 750 MB in 2002.
The Zip 250 drives were available in a wide variety of interfaces; parallel port, USB 2.0 and FireWire for exernal drives and IDE or SCSI for internal drives.
Although the disks looked identical to Zip 100 disks, they could not be used in the smaller capacity drive and are automatically ejected. They could however be read and written to by the later Zip 750 drives. Zip 250 drives could read and write to the older Zip 100 disks. A variant on the Zip 250, the Zip U250 was also launched in 2001; the U250 disks contained titanium particles in the media to improve the operation of the drives, and were also self-cleaning. The U250 discs were full compatible with Zip 250 drives despite their different shape.
All Zip variants were discontinued in 2003.