The five kinds of tanks available in World of Warcraft are: Protection Paladin, Feral Druid (Bear), Protection Warrior, Death Knight, and Brewmaster Monk. For solo play your pet may tank for you if you are a Hunter or Warlock, but they can't actually think for themselves.
In 5mans and raids, all four types are fine, and there's hardly a difference in effectiveness.
In a raid situation, the strengths and weaknesses of certain tanks come to light. Note that there is not a "best tank" per se, because classes achieve the same thing through a very different play style. Instead, check, which type of tank fits you personally.
Protection Warrior
The "allrounder" tank, the warrior used to be the only tanking class in the game, and it shows in their buildup. They are plate-wearers with shields, and build up massive amounts of mitigation. Their threat is caused by bleeds, thunderclaps and shield bashes. They have a few cooldowns in case things go downhill, but they rely less on them than Death Knights do.
Protection Paladin
Paladins have very strong AoE abilities, and are the masters of blocking with their shield. They wear Plate armor, and have among their talents the ability to cheat death once every few minutes. Paladins are also very good at picking up and kiting adds, such as in the Rotface fight.
Bear Druid
A Druid with bear talents is a massive wall of muscle and fur; they can wear leather armor only, but they gain more armor from it than other characters. They can Dodge, but they cannot parry or block since weapons and shields are meaningless to a bear.
Bear Druids make good soakers as well, such as offtanks on Blood Queen Lana'thel.
Death Knight
Death Knights use their runeblades to parry attacks, and can dodge them as well. They too are plate-wearers, but do not use shields. Death Knights are cooldown-based tanks, meaning they are not very strong unless they have one of their special abilities ready to be used. This makes the Death Knight good for people who can plan ahead well. They are also very strong against Magical attacks.
Brewmaster Monks
In Mists of Pandaria, the Brewmaster monk will be added, whose style of tanking seems to fall between a Druid and a Death Knight in that they rely on Agility and have a lot of cooldowns to use.
This cannot be answered at this moment because Ulduar raiding is everywhere currently progressing and the "best tank" can eather be the best geared one witch changes from week to week or the most skilled one witch can not be currently valued =)
The best class for tanking is probably the the mighty warrior.
I wouldn't listen to him
There are 3 people who I usually see thank (at my level) and that's the paliden, warrior, and druid. I use the warrior (suggest protection talents) and the druid. with the druid I usually do massive healing (since druids are good for overtime healing) then pulling a lot, or using starfire and then pulling.
As of cataclysm, the most preferred tanking class is a warrior, they also make very good dps.
Tankers' jobs are to take damage for other team mates and to lead the party into battle. To be a good tanker, you need good armor, high health, and high spirit(the higher spirit points you have, the faster your mana/health regenerates).
Druids and Paladins are also very good at tanking. Paladins have strong spells that dont take too long to cast and are powerful. They also have some healing moves so they can heal themselves if the healer in the team isn't very good(no offense to those of you healers). If you think you cant trust your healers, go with Paladin.
For druids tankers, they always use "Bear Form". Bear form has the same fighting style as a warrior(uses Rage as energy source etc.). They also have good tanking moves such as moves that attract enemies so they attack you, and also moves that attack multiple targets.
protection pally
tank
ME!!! im a tankadin called jnava look me up in bladesedge
Wow she is a hero wow she is the best. Wow
Wow Wow Wubzy. Yeah.
There is no 'BEST' class in wow. Each class has its strengths and weaknesses and can be overcome by another player who is better.
wow, how?
Magic wow - 3.3.5a molten wow - 3.3.5a best 2 I've ever played on^
mike posner song: Bow chika wow wow
I think SWTOR is much better than WoW. :D
The KV-2 is the best tank.
challenger 2 is the best tank in the world
bowwow