Article: Most chokes anymore are interchangeable because the inside of the end of modern barrels is threaded, so chokes can be screwed in and out at will. Generally, the following chokes are the most common:  Cylinder bore, which has no restriction, throws open but very uniform patterns. This is useful for close-range shooting. Skeet choke is appropriate for sport and target shooting. Full choke has a lot of restriction and throws very tight patterns when fed quality shot. However, when fed soft lead, a full choke tends to shoot uneven patterns. The pattern of the shot refers to how much the load spreads out during flight. The pattern changes depending upon the existence of a choke in the barrel. The tighter the choke, the more the lead will be affected. The more lead in a shotgun load, the more serious this effect is. Largely, this will depend upon your practice and your shooting style. If you're a very accurate shooter with hunting ambitions, a narrower choke might be appropriate to narrow the shot and ensure a clean kill. If you're a novice, a choke is probably unnecessary. Practice with different shot sizes, lengths, and combinations of different chokes with your shotgun. With a properly-sighted shotgun, track your shot patterns and accuracy to determine the best combination for your purposes.  If your patterns are the wrong size or don't have the density required to kill game, use a tighter or looser choke accordingly. If your patterns are uneven, you are probably trying to push too much soft lead through too small a hole. Sometimes less lead and a looser choke will actually allow you to be effective at longer range.

What is a summary?
Learn the basic types of choke. Determine the shot pattern appropriate to your purposes. Determine your optimum choke-shot combination.