DVD discs

A DVD-Recordable or DVD-R is an optical disc with a larger storage capacity than a CD-R, typically 4.7 GB (4.38 GB) instead of 700 MB, although the capacity of the original standard was 3.95 GB. Pioneer developed the 8.54 GB dual layer version, launched in 2005. A DVD-R can be written to only once, whereas a DVD-RW (DVD-rewritable) can be rewritten multiple times. The DVD-R format was developed by Pioneer in autumn of 1997. It is supported by most DVD players, and is approved by the DVD Forum.

DVD discs are the same diameter (120mm) and thickness (1.2mm) as a Compact Disc but a DVD can store 13 times or more data contained on a CD. Factoring in DVD's capability to record on both sides of the disc offers 26 times the storage capability a CD. Unlike a CD, a DVD is a bonded disc, made of two 0.6 mm substrates joined together.

At an average bit rate of 4.5Mbs, a single sided DVD disc has the playback capability of 133 minutes of the highest quality audio and video images. That's nearly 92% of all Hollywood titles ever made! Dual layer DVD disc can provide up to 4 hours of playback.

DVD discs will not deteriorate over time and are unaffected by magnetic fields (which can literally erase a VHS cassette).

Video : CD/DVD media types explained