Write protection is a setting of an audio, video or data tape, and of a diskette, to prevent accidental erasure by recording/storing over it. It may be a switch, a sliding hatch, or a tab that has to be broken out. In the latter case a piece of adhesive tape can be used to remove the protection. In 5.25 " and 8" diskettes a gap had to be covered with adhesive tape to protect it.

By applying write protection the memory turns (temporarily) into read-only memory.