A feature of many data storage devices that prevents them from recording or storing any data. Its use has been widespread for many years as a way to protect important data or recordings from being accidentally erased or recorded over. Historically media like cassette and VCR tapes have had removable tabs (tabs that break off) as a means of protection. A small switch inside the transport senses whether or not the tab is present and can allow or disallow recording as needed. On more modern devices, such as floppy disks, removable hard disks, and some memory cards there is a switch that can be enabled or disabled by the user. Other devices store protection settings in software form.