How do CDs and DVDs differ?
Though a DVD (Digital Versatile Disc) looks like a CD, it is actually two “half-discs” bonded together. It can contain data on one or both sides (dual-layer). Because of smaller pits and lands, as well as dual layers, DVDs can hold 7 to 25 times more information than a CD. A DVD can hold cinema-like video, better-than-CD audio, and computer data. DVD aims to encompass home entertainment, computers, and business information with a single digital format, eventually replacing audio CD, videotape, laserdisc, CD-ROM, and video game cartridges.
