Magneto-Optical Disk (MO Disk)

Why Trust Techopedia

What Does Magneto-Optical Disk (MO Disk) Mean?

A magneto-optical disk is a rewritable disk that makes use of both magnetic disk and optical technologies. It is similar to a magnetic diskette except for its larger size. Magneto-optical disks are seldom manufactured and used due to the advent of flash drives and DVD/CD drives, which are less expensive and have better writing time and reliability.


Magneto-optical disks are also known as magneto-optical drives and MO drives.

Techopedia Explains Magneto-Optical Disk (MO Disk)

One of the most well-known examples of a magneto-optical disk is the Sony MiniDisc.

The magneto-optical disk has the following features:

  • It is capable of having high data intensity by means of a magnetic read/write head and a laser.
  • Like diskettes, the magneto-optical disk allows multiple rewrites.
  • The driver for a magneto-optical disk can verify the information written to the disk and will report any errors to the operating system. This often results in faster reading but slower writing, although it helps make data storage more reliable.
  • The magneto-optical disk is a special removable disk.
  • The design of the drive allows the inserted disk to be exposed to the magnetic head on one side and to the laser on the other side.
  • Its writing speed is faster than that of diskettes, but is slower than that of CD/DVD drives.
    • Convenience and reliability are much better than those of diskettes, along with high data capacity.

Related Terms

Margaret Rouse
Technology Expert
Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.