The Data Crystal (also Data Chip, Data Bank, and other synonyms) is a general purpose external data storage for computer data. These develop along with the computer technology for storage and transferring of data and programs between computers.
There are many kinds of Data crystals, with different interfaces. Computer systems accept one to several of these data crystals. Interface translators of different kinds of data storage are generally available for a few credits.
Data on a data crystal usually remains readable for several years. Exposure to hostile environments can shorten this to days or weeks. There are archival data crystals that will keep data for a century or more.
The underlying system for data storage depends upon the Technology Level of manufacture of the crystal. Starting at TL–5 the storage is on various kinds of magnetic media. By TL–7 storage is an optical media. At TL–9 storage is solid state electronic media. At TL–12 the storage is holographic optical storage. With each TL advancement the quantity of data increases by one to three orders of magnitude.