Air Magic

Air Magic is an Elementalist secondary attribute meaning that any character with an Elementalist for their primary or secondary class can put points into this attribute.

Guild Wars Description
"No inherent effect. Many Elementalist skills, especially spells which deal lightning damage to and debilitate a single enemey, become more effective with higher Air Magic."

General Description
Air Magic has been dubbed the "PvP attribute" due to its effectiveness in PvP battles. The reason for this effectiveness can be garnered from the Guild Wars description - Air Magic spells deal large amounts of damage to and debilitate a single enemy. In PvP, when your entire party is focused on taking out that one protection Monk, it really helps to cast Shock to deal damage as well as knocking them down.

Air Magic is all about one thing: damage, damage, damage. Oh, and throw in some knockdowns and blindness in there just for fun. Chain Lightning is one of the most powerful skills in the game, dealing high amounts of instant damage to up to three targets. By comparison, the elite skill Lightning Surge is simply a slower, more easily countered spell that only damages one target and has no armour penetration (they cost the same amount of mana and have the same casting times). As a result of this, some PVP teams can be seen with 3 or more mages dedicated entirely to using Chain Lightning, using Air Magic skills to blind and knockdown while they wait to use chain lightning again.

Blinding Flash blinds a target, which is an absolutely devastating condition to a Warrior if the warrior has no way to heal itself of it. Many Air Magic skills knock down foes, effectively canceling all their actions and allowing you time to escape or deal more damage, including Whirlwind and Thunderclap to name a couple. However, the real power of the Air Mage is in the huge damage to a single target (or in the case of chain lightning, three targets) that the attribute's spells are capable of dealing.

However, Air Magic is a kind of one-trick pony, lacking any skills that heal or protect the caster in anyway. Also, a great many Air Magic skills cause exhaustion, something that can eventually be crippling to a mage. Finally, Air Magic lacks any skill that does damage over time, so skills that prevent Spike Damage such as Protective Bond and Protective Spirit can render a pure Air Mage almost harmless.