Krewes are social organizations that play a central role in the celebration of Mardi Gras in New Orleans. Each krewe organizes parades, balls, and other festivities, often featuring elaborate floats and costumes. Members of krewes typically participate in these events, showcasing their creativity and community spirit. Founded in the 19th century, krewes often have unique themes and traditions. Some of the most famous krewes include Krewe of Rex and Krewe of Zulu. Membership can be exclusive, with some krewes requiring invitations or specific qualifications to join, fostering a sense of camaraderie among members.