[jyl]

Stew: usually little pieces, submerged in liquid, you usually consume the liquid.

Braise: usually bigger pieces, not submerged in liquid, usually discard the liquid.

The piece size part is, I think, the most flexible distinction. I like to braise pork spare ribs, they are little pieces. And I'll stew a beef shank, that's a pretty big piece. The consuming the liquid part, to me, distinguishes stewing from boiling. You boil in plain water that is discarded. You stew in some sort of flavorful liquid - stock, wine, beer - that gets more flavorful so you really should consume it, either in the classic bowl of stew or, as with the shank, by subsequently reducing the liquid down to a sauce.

Just my opinion, I never went to culinary school or anything.