You perceive a typo in the text you just typed, and correct it, but then it turns out the original text was correct, and your error was in the rereading. You've just made a rereado.
Rereados are nothing to be concerned about:

It dsoen't rlaley mtater.

Sboodemy snet me an eiaml rentcely rdineming me taht it's olny the ltreets on ehetir end taht metatr. The oens in the mdlide you can put in whvaeter oredr you wnat.
by Insufficient Postage April 26, 2006
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