HD DVD May 2008, both companies announced they would stop manufacturing dual-compatibility drives. A few computer manufacturers (such as HP and Acer) sold computers with combination HD DVD/Blu-ray Disc drives. LG marketed a Blu-ray writer that also read HD DVD discs (but could not write to them). HD DVD competed primarily with Blu-ray Disc. Both formats were designed as successors to DVD, capable of higher quality video and audio playback, and of greater capacity when used to store video, audio, and computer data. Blu-ray Disc and HD DVD share most of the same methods of encoding media onto discs with each other,
Optical disc a protective layer read by a focused laser beam , filed 1972, issued 1991. Kramer's physical format is used in all optical discs. In 1975, Philips and MCA began to work together, and in 1978, commercially much too late, they presented their long-awaited Laserdisc in Atlanta. MCA delivered the discs and Philips the players. However, the presentation was a commercial failure, and the cooperation ended. In Japan and the U.S., Pioneer succeeded with the videodisc until the advent of the DVD. In 1979, Philips and Sony, in consortium, successfully developed the audio compact disc. In 1979, Exxon STAR Systems in