The various aids and devices used to control, regulate and guide traffic may be called traffic control devices. The general requirements of traffic control devices are attention, meaning, time for response and respect of road users
The traffic control devices installed along the road should be well within the field of vision of the drivers who are driving their vehicles at the design speed or at legal speed limit, these devices should distinctly draw the attention of the drivers and should convey the meaning without any ambiguity The most common among the traffic control devices are.
1) Traffic signs
2) Traffic signals
3) Road Marking
4) Traffic Islands
Regulatory signs : Regulatory signs are also called ‘mandatory signs’ .These signs are meant to inform the road users of certain laws, regulation and prohibitions. The violation of any regulatory signs is a legal offence and Is punishable as specified.
All regulatory/ mandatory signs are circular in shape, with only two exceptions they are 1) ‘Stop sign of Octagonal shape 2) ‘ Give way sign ‘ in the shape of an inverted triangle
Informative signs: The Informatory Signs are rectangular in shape. These signs are used to guide the road users along routes, inform them of destination and the distance, thus providing with information to make travel easier, safe and pleasant.
The colors chosen for informatory or guide signs depend on the classification of the road. For national highways and state highways, the informatory signs shall be of green back-ground with the borders, legends and word messages in white colour. For all other categories of road such as MDR, ODR and village Road these sign shall have white back-ground with borders, legend and word message in black colour.