If that's not the most pompous post in the world I don't know what is.
From your own link, I quote.
Zone Defense
Zone defense is different from man-to-man defense in that, instead of guarding a particular player, each zone defender is responsible for guarding an area of the floor, or "zone", and any offensive player that comes into that area. Zone defenders move their position on the floor in relationship to where the ball moves. Their are advantages and disadvantages of zone defenses. For example, you can often stop dribble-penetration and protect the paint with a 2-3 zone, but you give up some pressure on the outside. See "Zone Defense" for details. Zone defenses can be categorized based on the defensive "set" that you use (2-3, 1-2-2, 3-2, 1-3-1, etc). Rebounding out of a zone defense is also important. See Zone Defense Rebounding