A magneto-optic disk, also commonly known as a MO disk, is a type of optical disk that uses magneto-optical technology to store data. MO disks have been used in the past as a form of data storage, particularly for archival purposes in industries such as healthcare, finance, and government. However, as technology advanced, MO disks have become less popular and have largely been replaced with other storage solutions, such as hard disk drives and flash drives. Synonyms for magneto-optic disk include magneto-optical drive, MO storage, magneto-optical disk memory, and MO media.