Paladin builds can be either Holy, Protection, or Retribution. Holy leans towards either healing or spellcaster DPS, Protection leans towards tanking, and Retribution leans towards melee DPS.
Holy
With good healing gear, paladins of any spec can provide reasonable healing. However, healing dungeons and raids should be done by holy paladins specializised in healing (so called Healadins).
Healer (Healadin) (31/5/0)
Purpose
Raiding and Dungeons (can also be used as a leveling spec. by doing dungeons)
Holy is not only viable for healing, but also for dealing damage. These paladins (so called Exordins (previously Shockadins)) cast spells to harm their enemies. The paladin attacks enemies with spells such as [Holy Shock] and [Exorcism], for which [Denounce] is crucial: Holy dps can't be found under level 31.
Paladins are one of the four classes in the game that can be adapted to absorb damage like a sponge and keep others from harm. They are particularly famous for the ability to tank multiple (10+) mobs at the same time. Besides, Paladins are also well known for their ability to survive with their unique combination of invulnerability, plate armor and healing spells, which makes them very good for AoE farming.
Retribution paladins are excellent DPS offenders in PvE and PvP since the major retribution buffing in Patch 2.3.0 and Patch 3.0.2. The instrinsic high survivability of paladins coupled with the potential of high burst damage provided by the Retribution tree make them capable of disposing almost any classes one on one and valuable both in dealing and absorbing damage in group PvP. In PvE, besides the high damage output, they also provide various useful utilities to their party members.
[Crusader's Might]
[Bestow Faith]
[Light's Hammer]
[Holy Shield]
[Redoubt]
[Blessed Hammer]
[Zeal]
[Righteous Verdict]
[Execution Sentence]
[Saved by the Light]
[Judgment of Light]
[Holy Prism]
[First Avenger]
[Crusader's Judgment]
[Moment of Glory]
[Fires of Justice]
[Blade of Wrath]
[Empyrean Power]
[Fist of Justice]
[Repentance]
[Blinding Light]
[Unbreakable Spirit]
[Cavalier]
[Rule of Law]
[Blessing of Spellwarding]
[Eye for an Eye]
[Divine Purpose]
[Holy Avenger]
[Seraphim]
[Sanctified Wrath]
[Awakening]
[Hand of the Protector]
[Consecrated Ground]
[Selfless Healer]
[Justicar's Vengeance]
[Healing Hands]
[Glimmer of Light]
[Beacon of Faith]
[Beacon of Virtue]
[Righteous Protector]
[Final Stand]
[Final Reckoning]
Holy
[Holy Shock] and 
[Exorcism], for which 
Protection
Retribution
Icy Veins Holy, Protection, and Retribution Paladin Raiding Guides (Mists of Pandaria)
