What is jitter?

What is jitter? Is there an online audio encyclopedia available to look these things up? Thanks!
Sugar's right. But short def: Timing error(s) in the digital data stream-- it can produce distortion if bad enough. Cheers. Craig
Budrew - if you would like to understand "jitter" there is an outstanding article available on Stereophile's website. The URL is: http://www.stereophile.com/fullarchives.cgi?368
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