[bob jenkins]

Originally posted by Mark Dexter
Ah, the beauty of commas.

Reference:
My grandmother, who snorts crack, is 82 years old.
-vs-
My grandmother who snorts crack is 82 years old.

and

I'd like some beef jerky.
-vs-
I'd like some beef, jerky.

Grammar rule #1: Don't use commas, which aren't necessary.