A totem is the primary tool used by a Shaman as an instrument of war. Characterized by their immobility and area of effect, the totems embody the Shaman's mastery over the elements. Some totems possess destructive power while others aid and assist allies. Shamanistic cultures outside those of the Horde and Draenei also possess the ability use totems in battle.
Totems are unique to the Shaman, and must be obtained by completing certain quests. A Shaman can use one totem of each element at any one time: Earth (Nature-based spells), Fire (Fire-based spells), Water (Water/Frost-based spells) and Air (Nature-based spells). Once a totem is put down it cannot be moved, but a new totem can be used to replace it. In other words, the Shaman player can activate a spell that uses the Earth totem, another spell that uses the Fire totem, a third spell that uses the Water totem, and a fourth spell that uses the Air totem at the same time; however, the player cannot activate two spells that use the same totem because the last spell will override the previous one. Although the Shaman's totems are summoned and fixed near the caster, a Shaman player can place a totem while moving. A totem's effect is only active within a certain radius of the totem (making it a hybrid version of Point Blank Area of Effect and Ground Targeted Area of Effect). The totem can be planted underwater, and appears floating at the foot level of the character. Totems are immune to AoEs and DoTs, and must be specifically attacked to be destroyed.
In order to cast any totem spell, the Shaman must be carrying around a Earth Totem, Fire Totem, Water Totem, or Air Totem as appropriate for the totem spell they wish to cast. Shamans must complete a quest to receive each totem. These quests have several steps and usually require travel to a variety of places. After receiving a totem, the Shaman will be able to cast all totem spells for the corresponding element. The Shaman must keep the totem in a bag with them at all times in order to cast the totem spells for that totem type. The only exception to this is if the Shaman has a relic totem that has the "Counts as an Air, Earth, Fire, and Water Totem" comment (such as Totem of Lightning and Totem of Healing Rains) equipped or in their bag.
Totems only trigger a 1 second GCD as opposed to the regular 1.5 second GCD. Totems are also considered Physical spell school so they can be dropped even when silenced.
In Wrath of the Lich King
As of patch 3.3 each of the horde races have unique totem artwork. 
The first totem received by the Shaman. It allows the Shaman to use totems which do things like enhance defense/offense, slow enemies, and taunt them.
- Gained at Level 4
|Earth Totem Spells|
The second totem received in the Shaman's development. This totem is primarily used to deal damage.
- Gained at Level 10-13
|Fire Totem Spells|
The third totem received in the Shaman's development. This totem is used for restoration-type effects.
- Gained at Level 20-23
|Water Totem Spells|
The final totem received in the Shaman's development. Like the Earth Totem counterpart, it allows totems to enhance certain defensive/offensive aspects. Note: The Horde Air Totem quest doesn't seem to be complete, so the NPC in Thousand Needles just gives it to you. It's not a bug.
- Gained at Level 30
|Air Totem Spells|
Which Totems to Drop?
Since patch 3.0, and most shaman totems affecting the entire raid, sorting out which Shaman drops which totems in the raid can be a small task. The following applies regardless:
- Totems do not stack. Two does not mean more Spellpower.
- Totems that have been enhanced by talents will overwrite Totems that aren't.
That being said, the question now falls to, which Shamans drop which Totems?
- If an Elemental Shaman is present, he/she should be dropping . All other Shaman can drop damage dealing totems like or .
- If no Elemental Shaman is present, but at least one Enhancement Shaman is, with , he/she should be in charge of . All other Shaman can drop damage dealing totems.
- If no Enhancement Shaman has Enhancing Totems, but a Restoration Shaman is present, then the Restoration Shaman drops Flametongue Totem.
- If only one Shaman is present, that Shaman should drop Wrath or Flametongue depending on spec.
- If the situations calls for Frost Resistance, let the Paladins with handle, otherwise, Restoration Shamans, then Enhancement Shamans followed by Elemental Shamans should drop .
- All Shaman should drop as they see fit (no risk of breaking Crowd Control, long winded boss fights, etc.).
- Casting Specs (Resto, Elemental) should handle , while Enhancement should handle .
- If the situation calls for it, ALL Shaman should drop , regardless of spec as this only covers your group and not the raid.
- If Paladins are giving to the Shamans, is the only thing you should worry about.
- If Paladins are not giving Wisdom to Shamans, ask for a small wisdom (), if there are enough Paladins (Kings should NEVER be overwritten with a small any buff), or drop or based on who is in your group.
- If the situation calls for it, ALL Shaman should drop regardless of Spec.
- If the situation calls for Fire Resistance, follow the same steps with Frost Resistance above.
- Restoration Shamans should drop as they see fit.
- Like Earth totems, Casting Specs should handle , while Enhancement should handle .
- If the situation calls for it, ALL Shamans, regardless of Spec, should cast .
- If the situation calls for Nature Resistance, follow the same steps with Frost Resistance above, but replace the Paladin's Aura with the Hunter's .
- ^ http://www.worldofraids.com/news/169.html
- ^ http://www.wow.com/2009/10/02/patch-3-3-ptr-new-totems-for-trolls/