What is VCD you ask? I'll give you the short explanation. VCD is short for Video Compact Disc. Although not prevelant in the US, the format is quite popular elsewhere in the world, especially China and Maylasia. VCDs are actually very similar to DVD. The main difference is that VCDs are written to 650-700 mb CDs (the same type of CD used for audio CDs and computer CDROMs) where DVDs are a new type of 4.7+ gig disc. VCDs can be played on any computer with a CDROM drive, many DVD players, Sony Playstations with a special add-on, and of course dedicated VCD player equipment.
The video is encoded using mpeg-1 standard at 1150 kbps. The image is 352x240, half the resolution of DVD both horizontally and vertically. It seems small but is surprisingly sharp. I would say that VCD is equivalant to VHS at SP recording speed. The image is not as sharp as VHS, but is more stable and less noisy. The audio on a VCD is mpeg-1 layer-2 (mp2) 224 kbps, and of course it is stereo. It's very similar sounding to an mp3. A VCD can hold about one hour of video on a disc. You can randomly access chapters on a VCD similar to a DVD. And best of all, it never wears out like a VHS tape.
One great thing about VCD is that many titles that are out of print or just not on DVD or laserdisc can be found on VCD. I recently got Disney's Lion King on VCD as well as the Star Wars Trilogy. Great stuff! And they are CHEAP!
SVCD is a newer standard that is very close to DVD in picture sharpness, but more limited in bitrate. You really need a clean video source to make a decent SVCD. You might notice some blocking artifacts in high action scenes. SVCD is almost identical to VCD except the image is 480x480. Not as many DVD players can play an SVCD, but still many can. Also, you need special player software to play an SVCD on your computer. SVCDs are encoded using mpeg-2 (the same as DVD). A software DVD player might play an SVCD. SVCDs can hold about 50 minutes per disc.
If you want the long explanation, do a Google search for VCD, or visit www.vcdhelp.com. :-)