Nesso wrote:
Well to go more in depth with what Yuri was saying:
Warrior - Best tank in the game hands down if protection spec. Very good PvE dmg as Fury spec, Mortal Strike spec is the way to go if you want to go for PvP. Both fury and MS spec make decent off-tanks, protection spec does crap dmg.
Rogue - Has a nice variety of tricks, stuns are a pretty big part of their moves. Other tricks include blind, vanish, and saps, which are pretty nice for PvP but on a long cooldown (which is what kills them in 5v5 arenas, although they excel in 2v2 and 3v3), Other than that, they are arguably the most singular class in the game, DPS is what they excel at, and DPS is what they mostly will do.
Priest - You are either a healer or DPS, you can try to be one or the other, but those respec costs will pile up. Healing priests have the most variety of different type of heals for each situation. Shadow priests are good DPS, their biggest strenght comes from the synergy they provide to your group, they are essentially mana and hp batteries, and greatly complements a warlock because they provide each other with debuffs that increases their shadow dmg.
Druids - They have a wide variety of heal over time spells, and one big heal. Full healing spec gives you the ability to shift into tree form, which makes you only able to cast HoT spells, but at a cheaper mana cost, and it also gives your group an aura that increases healing recieved from heal spells. Feral specced druids make very good tank as bear form, second only to protection warriors, they also have the option of going into cat form for decent DPS.
Mage - Great DPS, Crowd control and AE, not much to say really... frost spec provides survivability, control, some burst dmg, pretty much the pvp spec for mages. Fire is all about efficient dmg, great burst dmg and AE. Arcane spec is there... I guess as a secondary spec or hybrid spec.
Paladins - You will mostly heal as a paladin honestly, a blessing for almost every situation imaginable and their aura are nice. They are very mana efficient healers, it's very hard for a healing paladin to go out of mana. A very good support class for both PvE and PvP. Their problem... almost everyone will expect you to be healing spec.
Hunters - Ranged / Pet class. Essentially another DPS class, has some crowd control and very annoying AE snares cause of their traps especially if survival spec. Good ranged burst dmg, class that has the least to worry about aggro, pet makes for a decent solo grinding tank and good supplemental DPS.
Shamans - Their roles vary a lot depending on their spec, only one thing remains constant thru their specs though, and that's their support abilities. Bloodlust is yum, totems that increases your groups DPS, mana regen, etc. Most common spec is healing spec, followed by elemental (nuking) spec, enhancement (melee spec) is mostly used for grinding and lvling.
Warlocks - DPS / Pet class. They have great DPS, good crowd control and good AE. Most of their dmg is done by DoT spells, they have a wide variety of them. They also have debuffs that increases the dmg a mob takes from spells. Like mages all of their specs are about dmg, affliction specializes in DoTs and Debuffs, Demonology in warlock/pet synergy and survivability as well, and destruction specializes in nuking/ burst dmg.
That's just a not so brief overall of each class. The important question is , what kind of class archetype do you find most enjoyable and fun?
Oh... hi!
Actually a well geared and played prot pally is an extremely efficient off tank and makes for really easy burst dps on trash mobs since they can generate a hell of a lot of threat quick as shit. Although, good prot paladins are 1 in a million and most guilds will look to them to be healers 99% of the time.

other than that.... pretty much hit everything right on the button.
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