Lice are tiny, wingless insects that live on the hair and scalp of humans. They feed on blood and can cause itching and discomfort. There are three main types of lice: head lice, body lice, and pubic lice. Head lice are the most common and are often spread through close contact or sharing personal items like hats and combs. Lice do not carry diseases, but their presence can lead to secondary infections from scratching. Treatment usually involves special shampoos or lotions designed to kill lice and their eggs, known as nits. Regular cleaning of bedding and clothing can help prevent reinfestation.