Buses and trains has similar infrastructure. It is a medium commonly used by advertisers to reach the public with their message. Usually, this takes the form of promoting commercial brands, but can also be used for public campaign messages. Buses may also be used as part of a political or promotional campaign, or as a tool in a commercial enterprise. It takes the form of advertise the commercial brands, this will be used for the purpose of public messages. It acts as the tool in expertise the commercial side.