Compact disc sized, 5-inch diameter optical disc capable of holding digital video and audio information for movies, music, computer games, and more. DVDs hold digital video using MPEG-2 compression and digital audio using primarily AC-3 (Dolby Digital surround sound) or DTS. VDs offer the purest, highest quality recorded video for consumers. They offer up to 525 horizontal lines of resolution. Additionally, DVDs store video information in its component format resulting in the highest quality video output (component video avoids comb and/or notch filters used to break apart composite signals resulting in signal degradation). VDs use pulse code modulation techniques similar to those employed with CDs and laserdiscs to store information. DVDs, however, are able to store more thanks to smaller pits and closer spacing between the tracks (requiring a smaller laser beam) along with advanced compression techniques. DVDs come in multiple varieties capable of storing information on one side of the disc, on two layers on one side of the disc, on two sides of the disc, and on two layers on both sides of the disc. VDs are being used both in home theater situations and in personal computers. Thanks to their versatility, they can be used to store any digital data from music and movies to games and programs. As a video format, DVD surpasses all others in terms of quality, performance and versatility. DVD can play video from multiple angles, in multiple languages and/or with multiple soundtracks, and with subtitles in multiple languages (when these features are included on a given disc). DVDs also feature on-screen menus many of which allow access to additional features such as theatrical trailers (previews), additional scenes, alternate endings, “how they did it” documentaries and more. DVDs are also able to store video in a traditional 4-by-3 aspect ratio, a letterboxed format, or an anamorphic format designed to take advantage of widescreen 16-by-9 aspect ratio televisions such as digital televisions for SDTV and HDTV. VDs are not currently available as a recording format like the VCR (although there are recordable DVDs for computers), however, that feature is being developed. DVDs are easy to store and last for many, many years with no signal degradation (assuming they are not abused, warped or irreparably scratched). With digital video and digital surround sound audio, DVD is the premier audio/video format available today.