Eyes were the primary visual organ of many sentient and animal species. Most species possessed a single pair of eyes located on their head, although some species, such as Abyssin, had only one eye, and others, like the Harch, possessed several pairs. Yet other species, like the Melitto from Li-Toran, had no eyes at all, relying on other organs to navigate. The droid equivalent to an eye was a photoreceptor.
When tutoring Luke Skywalker in the use of the Force, Obi-Wan Kenobi warned him that his eyes could deceive him and suggested not to trust them. To prove his point, he blindfolded Skywalker, after which Skywalker was successful in deflecting shot from a training remote with his lightsaber by drawing upon the power of the Force.