Floppy disk and Optical disk

Floppy disk noun - A small plastic magnetic disk enclosed in a stiff envelope with a radial slit; used to store data or programs for a microcomputer.

Optical disk and floppy disk are semantically related In some cases you can use "Optical disk" instead a noun phrase "Floppy disk".

Optical disk noun - A disk coated with plastic that can store digital data as tiny pits etched in the surface; is read with a laser that scans the surface.

Floppy disk and optical disk are semantically related in computer storage topic. You can use "Floppy disk" instead a noun phrase "Optical disk".