DC offset?

[Jhurlbs81]

OK, I have a basic understanding of this, but what would cause a wav to be offset high or low?  Is this something that ever comes up and needs to be corrected?

Thanks,
Jesse

[friday]

"Inaccuracies in the A/D converter or conversion subsystem that produce a slight output offset voltage. As with analog circuits, a processor that provides lots of gain (like a distortion plug-in) can turn a small amount of offset into something major."

http://www.harmony-central.com/articles/tips/eq_dc_offset/