A passive ability is an ability that is always active and doesn't require user interaction to use. Usually, they are not shown in your spellbook or tooltips, but some are. Many talents and racial traits are passive abilities. They are sometimes known as an innate ability. Passive abilities on items or mobs are sometimes called powers.

Non-racial ability examples
  • Most item bonuses and buffs are passive abilities like "+5 Strength" or "Improves your chance to hit with spells by 1%".
  • Many talents add passive abilities like the [Safe Fall] rogue ability (reduces damage from falling).
Profession ability examples;
Class ability examples

With the release of Patch 4.0.1, when a character chooses a class specialization, they automatically get related passive abilities.

Racial ability examples