Contact lenses are thin, curved discs made of plastic or silicone that are placed directly on the surface of the eye. They are designed to correct vision problems such as nearsightedness, farsightedness, and astigmatism. Unlike glasses, contact lenses provide a wider field of vision and do not fog up or get in the way during physical activities. There are two main types of contact lenses: soft lenses and rigid gas permeable lenses. Soft lenses are flexible and comfortable, while rigid lenses offer sharper vision. Both types require proper care and hygiene to prevent eye infections and ensure comfort during use.