The WoW Shaman is a hybrid class capable of fitting into three very distinct different roles depending on the talent specifications they choose. The three talent trees are elemental, enhancement and restoration and each one provides for a particularly unique role for the character, making it one of the most interesting and rewarding classes to play.
The WoW shaman is unique for a number of reasons but most notably because they use totems for buffs and part buffs rather than spells which are cast directly on themselves and others. The only disadvantage is that these totems can easily be destroyed under most circumstances.
Elemental shamans are primarily concerned with putting out great amounts of ranged damage. Investing some talent points in this tree will dramatically increase the power of your offensive spells, their critical strike chances and the mana cost of them. Elemental shamans are almost on par with mages and warlocks when it comes to raw damage output, providing they have the right set of gear.
Enhancement shamans are also big damage dealers, but the talents available in this tree are designed to enhance the melee capability of the shaman, making them stronger and their melee abilities more powerful, making them more akin to warriors.
Shamans do have a steep learning curve due to their relatively complicated set of talents but they can also be a very rewarding class to play and they are no longer just limited to Horde players as they used to be.
If you are thinking of playing a WoW shaman, then you generally have to be prepared to fit into a healing roll towards the end of the game, but with dual talents, that should not be a problem for many players. It is also not a good choice for a player who is just starting out with their first character. Hybrid classes in general are this way.
