Intraocular lenses (IOLs) are artificial lenses implanted in the eye, typically during cataract surgery. They replace the eye's natural lens, which may become cloudy due to cataracts, leading to vision problems. IOLs help restore clear vision and can be customized to correct various vision issues, such as nearsightedness or farsightedness. There are different types of IOLs, including monofocal, multifocal, and toric lenses. Monofocal lenses provide clear vision at one distance, while multifocal lenses allow for clear vision at multiple distances. Toric lenses are designed to correct astigmatism. The choice of lens depends on individual vision needs and lifestyle.