 In 2005, Raissa D'Souza found that for some traffic densities, there is an intermediate phase characterized by periodic arrangements of jams and smooth flow.In the same year, Angel, Holroyd and Martin were the first to rigorously prove that for densities close to one, the system will always jam.Later, in 2006, Tim Austin and Itai Benjamini found that for a square lattice of side N, the model will always self-organize to reach full speed if there are fewer than "N"/2 cars.