Some contact lenses are made to be worn just for a day and then disposed of, while others can be worn for a long period of time. While your eyes can get dry from extended use, contact lenses have gotten more breathable over time and solution have been created to keep them hydrated. Hard contact lenses can be more durable, but also are more uncomfortable and dryer on the eye. RGP lenses are made of a good mix of materials that are more permeable to oxygen for comfort. Soft contact lenses are the most malleable, but can be harder to manage because of their squishy feel.
Larger rigid gas permeable contact lenses designed to vault over the cornea. These contacts help patient that has an irregular cornea such as Keratoconus.