The ciliary body is a part of the eye located behind the iris and is responsible for producing aqueous humor, the fluid that fills the front part of the eye. It also contains the ciliary muscle, which helps change the shape of the lens for focusing on objects at different distances, a process known as accommodation. Additionally, the ciliary body plays a crucial role in maintaining intraocular pressure and providing nutrients to the lens and cornea. It is connected to the iris, which controls the size of the pupil, and is essential for overall eye health and function.