Grilling is done quickly over a high heat using briquets or gas. BBQ, in my book, is low and slow. Some cuts of meat can take many hours of smoking over indirect heat. Typically meat that is BBQ'd is rubbed with a seasoning and then slowly smoked, using fine hardwoods at a temperature somewhere between 180 and 225 degrees. At some point in this process the pitmaster may choose to add his or her sauce. Both Rubs and Sauces are highly personal and very few pitmasters will share their secret recipe for either. I'm not that worried about it because all of my "secrets" were either learned directly from others or adapted to my own taste from another recipe. At some point I'll post these.
Smoking Various MeatsIt is possible to cook higher and quicker with smoke but usually the meat just doesn't turn out as good if it is rushed. Slow smoking allows the meat to breakdown (tenderize) and retain more juices than grilling and then the wonderfulness of smoke is added.
Smoke meat is more flavorful and it's also obvious when you see the tell tell smoke ring, a red ring around the edge of the meat that indicates it was slowly smoked, rather than grilled.
Smoked Beef Brisket
Smoked Pork Rib
For now I guess that's it. Just some basic thoughts on Grilling and BBQing, both of which are wonderful ways to cook meat.
Oh..... one last thing. For you lifelong members of PETA, I'll simply say, "if God didn't want us to eat animals then he wouldn't have made them out of meat."
"May your Root Beer mug overflow and may you feel the need to wipe the BBQ sauce off your face."