Perception
This skill encompasses a character's alertness, awareness, and perceptiveness of the world around them. Creatures that are actively hiding from other creatures make Stealth checks against the Perception DCs of those from whom they are hiding while creatures that are actively searching for something roll Perception checks against the Stealth DC of hidden creatures or object. Perception can also allow a character to see through illusions. It does not allow a character to comprehend the importance or significance of creatures or objects which are not obvious, so many other skills often serve in place of Perception when trying to find something in plain sight or uncover clues.