Swap or Swop? Which do you use? Is one preferred or correct as opposed to the other or are both equally valid? [duplicate]
Solution 1:
In American English and British English swop is a variant spelling of swap. (See the also swop note at the top of the page.)
The copy of the NOAD I had on my Mac Mini explicitly said swop is a variant spelling of swap, and also reported swop as chiefly British.
Solution 2:
I know that "swop" is a variant, having seen it in manuals and help discussions like this, but I've never seen it used in real life (i.e., in US usage). Looks very UK-ish.