CD-DVD manufacturers manufacture compact discs. A CD-DVD is a device which plays discs produced under both video and audio technical standards. CD includes photo CD, video CD, super video CD, enhanced CD and audio CD. CDs and DVDs are used at homes for entertainment purposes, in computers in schools etc. CD, is known as compact disc, is a round disc used to store digital data. CDs now are used in write-once audio and data storage, rewritable media, Video Compact Disc and Super Video Compact Disc etc. Standard CDs have a diameter of 120 millimetres and the ability to hold up to 80 minutes of uncompressed audio.