A float is a decorated platform, either built on a vehicle or towed behind one, which is a component of many festive parades, such as the Maltese Carnival, the Macy's Thanksgiving Day Parade, the Key West Fantasy Fest parade, and the Tournament of Roses Parade. For the latter event, floats are decorated entirely in flowers or other plant material.
Parade floats were first introduced in the middle ages when churches used pageant wagons as movable scenery for passion plays. Artisan Guilds were responsible for building the pageant wagons for their specified craft. The wagons were pulled through out the town, most notably during Corpus Christi in which up to 48 wagons were used, one for each play in the Corpus Christi cycle.
The name is derived from the first floats, which were decorated barges that were towed along canals with ropes held by parade marchers on the shore.