floppy disk drive (FDD)
A floppy disk drive is a peripheral unit of a personal computer. A floppy disk drive can be an integral part of the computer or an external unit with its own housing. The drive contains the drive and control mechanics for receiving and driving the floppy disks.
It also contains the read/write devices, i.e. the read/write head as well as the stepper motor and the control system for its radial movement. The drive of a floppy disk drive operates only when the stored data is accessed. The floppy disk drives commonly used today are double-sided drives with two read/write heads that move together but are accessed independently.
The access times of floppy disk drives are around 100 ms, whereby the positioning time and the touchdown time are included in this time.
According to the floppy disk formats, there are floppy disk drives for 8", 5.25" and 3.5". There are also single drives and multiple drives.