School of Warriors

1) Fighter:
Fighters are flexible in their choice of weaponry. They're able to wield many kinds of close-combat weapons depending on the situation. Their combat style is comparatively easy to learn. This isn't to say that it is an easy class to master. With some flair they can outshine even the fanciest damage-dealing classes.

2) Knight
It's unfortunate that in most MMO games the tank is conceptually attractive but not so fun to actually play. The classes in Aion are classic in some ways, but they all have their quirks that make them stand out from the archetype. With the Knight, players will see different shades of the class as it absorbs more and more damage. It's truly a different sort of tank melee class.
 

School of Scouts
3) Ranger
Ranger is a utility class with many tricks up its sleeve, such as laying traps and sniping from afar. It's a well-rounded class with both melee and ranged skills as well as an aion kina to heal itself. Careful assessment of the situation is needed for a ranger to shine, for its many abilities can as easily get in the way for an unskilled player.

4) Assassin
We can more or less sum up the assassin class with the words: watch your back! Big damage within a short span of time - that's what the assassin is all about. However to get that proper use out of an assassin, swift positioning is extremely important.

School of Mages
5) Wizard
A powerful magic class with deadly nuking skills, but also extremely fragile up close. A wizard might prefer to be in a party for survivability but with some care it could also be a fast solo class.

6) Elementalist
An elementalist is not your aion kina summoner. As the name suggests, their tool of trade are the elementals that they manipulate at will. Get intimate enough with the elementals and you might very well become one.

School of Clerics
7) Priest
Priests are, of course, the masters of recovery. They posess many healing skills to aid their kin, but that's not all. With a solid set of skill combinations and a number of melee skills they may surprise you in the right situation.

8) Chanter
As a cleric, chanters can also heal to a certain extent, but their aion kina is in mysterious chants that boost the morale of nearby players. They're also known for effective melee skill combinations and all-around usefulness. It should be an attractive class for those that like to do it all.