Compact disc hits 25

August 17th will mark the 25th anniversary of the compact disc, now one of the most ubquitous removable media formats in the world. The CD was originally conceived as a music standard, and was the product of a 1979 collaboration between Sony and Philips, who based the technology on the LaserDisc video format. The anniversary is connected to Philips' pressing of the first commercial CD release, the ABBA album "The Visitors" -- but discs did not actually go on sale until November of 1982, when 150 mostly classical releases appeared in Japan. American and European launches took place in March of the following year.

The music CD has since formed the basis for numerous related standards, most notably the data-ready CD-ROM, which originated in 1985. In 1995 the DVD was created, uniting audio and data with more practical digital video uses. While still prevalent, this technology is now on the verge of being replaced with either HD DVD or Blu-Ray -- a struggle that mirrors the competition between VHS and Betamax in the 1980s.