Level represents the character's overall competence and capability. Most characters are 1st level, but some characters are of higher levels. A character's level is added to attribute checks and skill checks.
Characters of 1st to 5th level belong to the heroic tier. Characters of 6th to 10th level belong to the paragon tier, and have access to abilities that heroic tier characters do not. Characters of 11th level and higher belong to the epic tier, and have access to additional abilities.