This document discusses different types of traffic control devices used to regulate traffic, including signs, signals, markings, and islands. It describes three types of signs: regulatory signs that inform users of laws and regulations, warning signs in triangular shapes that warn of hazards, and informatory signs that provide guidance and information. It also outlines different types of traffic signals using red, yellow, and green lights and pedestrian signals. Road markings include lines, symbols and reflectors used to guide drivers. Finally, it discusses four types of traffic islands that separate traffic flows and guide vehicles, including divisional, channelizing, pedestrian loading, and rotary islands.