That annoying exhaust sputter.

[b]My question is, What causes that annoying backfiring, sputtering, sound from the exhaust? I plan on buying an exhaust system (Headers, cataylic Converter, Catback it i can find one). Will this cut out the backfiring?? The only thing i have on my car right now is a 3, maybe 3 1/2 inch aftermarket muffler. I searched the forum and came across some exhaust threads, but non of them pertained to my question. Thanks in advance.