By establishing a distance between them and the opponent, and maintaining it, it is possible for a player to limit the opponent's options by forcing them to play a certain way, or else take advantage of their character's effectiveness at certain ranges; this lets the zoning player take control of the match, as it will be easier to counter/punish/respond to whatever few attacks they can properly pull off at said distance, and then press the advantage.
Another essential quality of this "keep-away" strategy is being able to adapt; should the opponent find a way to beat the current tactic in use, the zoning player should have a plan ready to re-establish the desired condition. To this end, it is important that the zoning player learns the properties of each attack at their disposal, and those of their opponent's attacks. Learning the best timing for each attack is essential as well.
Zoning, Projectiles and "Spamming"Edit
While zoning is commonly associated with projectiles, especially those 'designed' for such a purpose (e.g. Chun-Li's Kikoken), they are not the only means of doing so; other attacks can be used to maintain a certain distance as well. In fact, Dhalsim is considered the pioneer of the "keep-away" strategy, due to his amazing reach (e.g. his crouching fierce) combined with a low speed and defense.
The association of zoning with projectiles has also resulted in comparisons to "spamming". A major point to remember in avoiding confusion of the two is that spamming relies on the same tactics without any form of adaptability, i.e. constantly throwing projectiles during the whole match; zoning, on the other hand, relies on varied tactics, maintaining pressure, and the ability to adapt to the given situation and the opponent's moves. A notable comparison is with a player who throws projectiles at any opportunity while not using any other moves, and with a player who throws projectiles and uses other long-ranged attacks only during specific moments.