Video CDs are ordinary CDROMs in a special format which contain MPEG-1 encoded video. For long times this type of CD was mostly known in Asia whereas Video CDs and the according players were mostly unknown in the USA and Europe. Since almost every DVD player can also play VCDs (and since the recordable Video DVD for a reasonable price seems still far away) VCDs are getting more popular everywhere. VCDs use a special type of CD sectors (mode 2 form 2) and have a special form of the filesystem.
http://www.os2world.com/cdwriting/
If you want to know more about VCDs, visit the http://www.geocities.com/Athens/Forum/2496/vcdfaq.html VCD FAQ or do a search in the web.
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