A diskette is a random access, removable data storage medium that can be used with personal computers. The term usually refers to the magnetic medium housed in a rigid plastic cartridge measuring 3.5 inches square and about 2 millimeters thick. Some older computers provide drives for magnetic diskettes that are 5.25 inches square, about 1 millimeter thick, and capable of holding 1.2 megabytes of data.
Magnetic diskettes are convenient for storing individual files and small programs.
However, the magneto-optical is more popular for mass storage, backup, and archiving. An MO diskette is only a little larger, physically, than a conventional 3.5-inch magnetic diskette.