Compact disc
Compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony and released in 1982. The format was originally developed to store and play only sound recordings (CD-DA) but was later adapted for storage of data (CD-ROM). Several other formats were further derived from these, including write-once audio and data storage (CD-R), rewritable media (CD-RW), Video Compact Disc (VCD), Super Video Compact Disc (SVCD), Photo CD, PictureCD, CD-i, and Enhanced Music CD. The first commercially available audio CD player, the Sony CDP-101, was released October 1982 in Japan.
History of Wikipedia
The first CD version containing a selection of articles from the English Wikipedia was published in April 2006 by as the "2006 Wikipedia CD Selection". In April 2007, "Wikipedia Version 0.5", a CD containing around 2000 articles selected from the online encyclopedia was published by the Wikimedia Foundation and Linterweb. The selection of articles included was based on both the quality of the online version and the importance of the topic to be included. This CD version was created as a test-case in preparation for a DVD version including far more articles. The CD version can be purchased online, downloaded as a DVD image file or , or accessed online at the project's website.