Powers are the special actions your character can perform, ranging from attacks, to healing, to support abilities like flying through the air.
Each power has a number of key words and rules associated with it. Page 54 of the Player's Handbook details how powers work and how to read their descriptions.
There are several classifications that separate powers based on when and how often they can be used.
- At-will powers can be used any number of times.
- Encounter powers can be used once per encounter, and are renewed after a short rest.
- Daily powers can be used once per day. You must take an extended rest to renew these.
- Utility powers are a special category of encounter and daily powers that fulfill support roles rather than direct attacking.