I am not an expert. These are a random assortment of Burning Man terms.
Darkwad
A person, riding a bike or not, who is on the playa at night but without any illumination.
Esplanade
The avenue between the city and the playa. Mutant Vehicles are not allowed on esplanade. Esplanade is a buffer between the city and the artwork on the playa.
Mutant Vehicle
The only type of vehicle participants can drive around the city and the playa. Vehicles must be suitably transformed to be mutant. They must be registered and approved ahead of the start of Burning Man, and inspected and licensed on site before they are allowed to drive.
Playa
The area where the Man and Temple reside, and all of the space surrounding it, except for Black Rock City. “Playa” means “beach” in Spanish, which might be a tempting original story (the first Burning Man was held on a beach in San Francisco), but that is not the origin of the word: playa refers to particular desert terrain, on which Burning Man sits.