More Information about DVD and the Digital Age.

DVD - stands for digital versatile disc. It records information as compressed digital data on one or more layers of optical medium and is read by a laser beam in the DVD device. Small, easily packaged & transported. Can store enormous amounts of data and costs pennies to manufacture. Data can be ANYTHING - music, moving image, still image, text, animation, you name it and all on the same little disc. The costs of creating the data, though, can be huge. Advantages are obvious. These things can store all the films that would rot in the cans in Hollywood, once they're remastered and transferred. Have a look in HMV and see all the old black & white stuff available, for example.Another great advantage of DVD is the quality of image and sound. Anything not digitally copied loses a little quality every time a copy is made. Because digital technology works on numbers, the numbers are always constant, so any copy is exactly the same as any other. Two million copies of a DVD of 'Return of the King' will all be exactly the same in terms of quality of image and sound. Same with video games, same with any type of DVD.
CD - stands for compact disc. Also stores data and is read by a laser in the CD device. See above but don't ask me how they're different because I don't know. No doubt some kind technology person will tell me in due course.
DAT files - digital audiotape files that record music digitally on to tape.
Digital TV - fast, high quality TV pictures processed through computerised images. They need to be received by aerial/satellite dishes, or via cable and have a 'de-coding' box to unscramble the signals & put them on your nice flat screen TV set. The one with the five speakers that annoy the neighbours and wake the baby up at two in the morning when you're watching 'Return of the King'. Add to this 'interactive TV', where the consumer can view and choose things like camera angles and replay the goals on live sport transmissions or vote Jordan off 'Im a Celebrity, Get Me out of Here'. Such fun for the bored couch-potato.Digital TV was launched around 1996 and now has three 'platforms' for reception - SKY digital (via satellite), Ondigital (BBC) via aerial and NTL (via a cable network). No doubt there will be more soon.Many options are available, like business video-conferencing and 'pay-per-view' for important live events (mainly sport).In development are 3D holographic TV and also plasma screens (worked by gas, not tubes). Video recorders were challenged by DVD technology, but also in development is a neat idea called the PVR or personal video recorder which will use a hard drive to store programmes recorded from TV for later playback. It will be able to 'profile' your consumption by tracking your preferences, so if you always watch East Enders, it will record it for you because it 'knows' you like the programme. By keeping a record of the channels you watch, it can also provide data back to market researchers, so you can be targeted for products and services.Digital radio - Until digital technology was developed all radio programmes were either AM or FM, processes which present the actual sounds generated, complete with crackles, hisses and atmospheric interference. Digital radio signals are translated into computerised digits so there is no distortion or interference, which means better sound quality.