Conventional signs and markings are visual means of providing information, guidance and instruction to travellers during their journey. Their objective is to promote the safe and efficient use of the transport system. Both signs and markings impart information but also have a role in the management of traffic. In many cases, signs and markings are used in conjunction with each other.

Signs and markings include:

• Upright signs - various types of upright signs with textual or graphical images, for information, regulation or warning

• Road markings – provided to channel traffic and to convey warnings, regulatory requirements or basic information
• Miscellaneous signs – including traffic signals, temporary signs and lamps to identify refuges or provide additional warning in cases of dangerous obstructions.

Common standards for signs and markings exist to help ensure that travellers can easily understand signs wherever they might be travelling.

Conventional direction signing can provide benefits to car users, and other traffic, by reducing journey lengths and travel times; direction signing can also be used to divert traffic away from environmentally sensitive routes.
Signs and markings are also important in road safety by providing information necessary to make safe decisions while travelling.

There is little direct evidence on their effectiveness but it is known that direction signing can help to reduce congestion, by reducing driver confusion, journey lengths and travel times, while regulatory signing can influence congestion by reducing the number of accidents that impede flows and generate delays.
Regarding markings on the road surface, research has shown that longitudinal road markings, including chevrons, can reduce speeds and accidents considerably. Overall, it can be concluded that markings are cost efficient, and instrumental in easing congestion and promoting safety.