Over the years, there have been many varieties of reel-to-reel tapes, tape cartridges, tape cassettes, floppy disks, hard disk cartridges, optical cartridges, hard drives and solid state drives. Today, the industry has standardized on SATA hard drives, NVMe solid state drives and USB flash drives. See
SATA,
NVMe and
USB drive.
The physical shape is half the standards issue, and for removable media, the cartridge or cassette cannot be inserted into the wrong drive. The other half is the recording pattern, which is invisible to the human eye and is written onto the tape, disk or SSD by the drive. For example, a flash drive can be inserted into any USB slot on any device; however, if the drive was formatted specifically for the Mac, it cannot be read by a Windows PC without a special program. See
format program,
magnetic disk,
magnetic tape,
optical disc and
standards.