Turn Undead

The Ability to send Undead away from you and your party. If the undead being turned is significantly less powerful than the cleric, then it is destroyed rather than turned.

Turn undead mechanics
1. Turning check:.

2. Turning damage:

Destroying undead:

There are also items, spells and enhancements which can help increase your turning ability by boosting your effective cleric level for turning. These bonuses are added all parts of the turn undead calculation that use Cleric Level:
 * a Sacred item, adds +2 enhancement bonus to your cleric level.
 * The spell Seek Eternal Rest will add a stackable +4 sacred bonus to your cleric level.
 * The cleric/paladin enhancement line of Improved Turning can add from 1 to 3 points to your cleric level.
 * The feat Improved Turning will add 1 to your cleric level.
 * The shield item Aegis of Flame adds 6 hit dice to those turned when equipped.
 * Armor of Command adds a bonus to Charisma based checks, which might include Turning attempts.

Cleric Enhancements
The Turn Undead feat can be used instead as "charges" for the following cleric enhancements:
 * Divine Cleansing: Activate this ability to grant another character a morale bonus on Fortitude saves for a short time.
 * Divine Healing: Activate this ability to give another character healing that persists over several seconds.
 * Divine Light: Activate this ability to deal light damage to the targeted undead creature instead of attempting to turn it.
 * Divine Vitality: Activate this ability to restore a small amount of spellcasting energy to another character.

The Turn Undead can also be used as charges for the following paladin enhancements:
 * Divine Might: Activate this ability to add +2 to damage for one minute.