The 5 1/4" floppy disk is one of two standard |data storage| media used in a floppy disk drives (the other is the |3 1/2" disk|). It consists of a circular disc of ~ferric oxide~-coated ~Mylar~, enclosed in a protective envelope of flexible plastic. An oblong aperture in the envelope allows the read/write head to access the recording media. A hole in the center of the disk accommodates the drive's spindle. This spins the disk to access the |data sectors|.
The drive's |read/write head| can recognize and alter the orientation of magnetic charges on the media. These charges represent |binary code|. The disk media is extremely sensitive, and can be damaged by heat, electromagnetic fields, or even contamination by fingerprints. To protect the disk, it usually is kept in a ~Tyvek~ or paper envelope. Common 5 1/4" "floppies" can store more than a million bytes of data.
