Contact lenses, or simply contacts, are thin lenses placed directly on the surface of the eyes. Contact lenses are ocular prosthetic devices used by over 150 million people worldwide, and they can be worn to correct vision or for cosmetic or therapeutic reasons. In 2023, the worldwide market for contact lenses was estimated at $18.6 billion, with North America accounting for the largest share, over 38.18%. Multiple analysts estimated that the global market for contact lenses would reach $33.8 billion by 2030. As of 2010, the average age of contact lens wearers globally was 31 years old, and two-thirds of wearers were female.