Questions about algorithms or programs that compute on multiple processing units simultaneously. Not to be confused with concurrent or distributed computing!
Common category tags are algorithms but also complexity-theory if the question is about parallel complexity (buzzwords include e.g. PRAM or NC).
Find a general introduction on fitting topics on Wikipedia.
In particular, contrast with concurrency and distributed-systems which have different focus. See these discussions for more information on this:
That said, if you run into concurrence issues in your parallel algorithm, certainly use this tag in addition!
