What is jitter?

What is jitter? Is there an online audio encyclopedia available to look these things up? Thanks!
Try searching old threads. This has been covered many times before.
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
Or you can Click Here to load the website.