Where can I find resources on proving algorithms correct? I'm looking for a formal treatment (hopefully I have enough background by now to absorb that). I keep seeing these proofs of algorithms and references to proofs of algorithms but everything is informal and I've never even seen a precise definition of "algorithm." I can't find much on Google or Mathworld. Judging by the online descriptions of courses about algorithmic proof, there must be plenty of information out there, but it's not very accessible. I'd appreciate any suggestions.