Traffic on roads may consist of pedestrians, ridden or herded animals, vehicles, streetcars, buses and other conveyances, either singly or together, while using the public way for purposes of travel. Traffic laws are the laws which govern traffic and regulate vehicles, while rules of the road are both the laws and the informal rules that may have developed over time to facilitate the orderly and timely flow of traffic.

TRAFFIC is a joint programme of World Wide Fund for Nature (WWF) and the World Conservation Union (IUCN). Traffic also works in co-operation with the Secretariat of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). The programme was founded in 1976, with headquarters now located in Cambridge, United Kingdom, and regional bases in Africa, Asia, the Americas, Europe and Oceania with national offices within these regions.