A Zip disk is a storage device resembling a 3.5-inch floppy disk, except that it is thicker and has a larger storage capacity. It is designed to provide the portability and convenience of a floppy disk, but with the capacity and reliability of a hard disk. It can hold from 100 MB to 750 MB of data, and is read by a compatible Zip drive. Unlike floppy disks, a Zip disk can only work with a Zip drive of the same capacity; a 100 MB disk can be read only by a 100 MB drive.