Optical:

Laser technologies have made it possible to develop digital data
storage systems (WORM, CD-ROM) that have the have the capacity
and flexibility to store a variety of information types (sound,
real-time video, images, text).  Because a laser device can read
a bit of data of microscopic proportions (40 u), extremely high
density optical storage is possible.  While a 5.25 inch removable
cartridge currently can hold 200 to 500 Mbytes of data per side,
laser optical systems are being developed that can accommodate 1
Gbyte of data per side.  Although data access times are slower
than those achievable with hard disk technologies, the data
retrieval time for optical disks has improved rapidly and
dramatically (faster than 40 msec).  The stability of data and
portability of immense information bases make the optical storage
systems appropriate for many applications.  Whole libraries, such
as that planned for the University of Southern California Center
for Scholarly Technology, will be optical disk based, with the
information accessed by remote computer terminals.  All resource
materials in the library, including books, audio recordings,
movies, slide collections, etc. will be eventually accessible
from anywhere in the campus network.

<ffile41>   Data Storage
<ffile46>   Magneto-optical
<cfile61>   Optical Disk Storage