Home > Glossary > CD
DVD Ripper

What is CD

CD

Definition of CD

A Compact Disc (also known as a CD) is an optical disc used to store digital data. It was originally developed to store sound recordings exclusively, but later it also allowed the preservation of other types of data. Audio CDs have been commercially available since October 1982. In 2010, they have been largely replaced by other forms of digital storage such as flash drives, with audio CD sales dropping nearly 50% from their peak in 2000.

Standard CDs have a diameter of 120 mm and can hold up to 80 minutes of uncompressed audio (700 MB of data). The Mini CD has various diameters ranging from 60 to 80 mm; they are sometimes used for CD singles or device drivers, storing up to 24 minutes of audio.

The technology was eventually adapted and expanded to encompass data storage CD-ROM, write-once audio and data storage CD-R, rewritable media CD-RW, Video Compact Discs (VCD), Super Video Compact Discs (SVCD), PhotoCD, PictureCD, CD-i, and Enhanced CD.

CD-ROMs and CD-Rs remain widely used technologies in the computer industry. The CD and its extensions are successful: in 2004, worldwide sales of CD audio, CD-ROM, and CD-R reached about 30 billion discs. By 2007, 200 billion CDs had been sold worldwide.

The Copy Protection of CD

The Red Book audio specification, except for a simple 'anti-copy' bit in the sub code, does not include any copy protection mechanism. Starting in early 2002, attempts were made by record companies to market "copy-protected" non-standard Compact Discs, which cannot be ripped, or copied, to hard drives or easily converted to MP3s. One major drawback to these copy-protected discs is that most will not play on either computer CD-ROM drives, or some standalone CD players that use CD-ROM mechanisms. Philips has stated that such discs are not permitted to bear the trademarked Compact Disc Digital Audio logo because they violate the Red Book specifications. Numerous copy-protection systems have been countered by readily available, often free, software.

Related Software

As we know, CD belongs to the video playing field, so here I recommend a good related software – Video Converter Factory Pro, it is a powerful and reliable video converter, it can both help you convert nearly all popular video formats and help you convert nearly all popular audio format besides CD. You can either choose to convert other video or audio formats to CD format or you can choose to convert CD format to other popular audio formats. With it, you will enjoy more from your CD resources.

Related Source

AVI MP4 MKV MOV MPEG MPG WMV RM ASF RMVB Real Video Video 3G2 3GP 3GPP M4V VOB DVD FLV VCD MOD CD Matroska

DVD Ripper

Featured Software
Hot Tags
WonderFox Soft
CopyRight @ 2009-2017 WonderFox Soft, Inc. All Rights Reserved. Home | About | Contact | Affiliate | Privacy Policy | Sitemap