The par combinator par::a→>b->b x par y Value(ie, thunk bound to x is sparked for speculative evaluation Runtime may instantiate a spark on a thread running in parallel with the parent thread Operationally, x par y y ypically, x Is used inside y: blurRows par(mix blurcols burrOws) All parallelism built up from the par combinator Value (ie, thunk) bound to x is sparked for speculative evaluation.  Runtime may instantiate a spark on a thread running in parallel with the parent thread.  Operationally, x `par` y = y  Typically, x is used inside y:  All parallelism built up from the par combinator. par :: a -> b -> b x `par` y blurRows `par` (mix blurCols blurRows)