Outdoor advertising is probably one of the earliest forms of advertising in existence. The earliest forms of outdoor advertising usually consisted of eye-catching signs prominently displayed on the exterior walls of houses. Archaeologists have found a number of such markers in the ruins of ancient Rome and Pompeii. One outdoor advertisement excavated from ancient Roman ruins was for a property to be rented, and another on a wall in Pompeii was a solicitation to travelers to the area.
Outdoor advertising has remained one of the most widely used media for branding and marketing messages for thousands of years, even as print, radio, television, cable and, more recently, the Internet have evolved.
The amount of advertising dollars spent on outdoor media in recent years -- which includes spotlight billboards, shelters, monopoles, subway posters, buses, airport ads and more -- is evidence of its ubiquity. -- has been growing rapidly at 25% per year since 1990, much faster than newspapers, magazines, radio and television. In a recent (2000) survey by Media Magazine, it was revealed that in China, outdoor is the second best medium after television for delivering messages to the masses.
Common types of outdoor media:
Single media - media that is usually purchased separately when outdoor media is purchased, such as spotlight ads, monoposts, neon, walls, triplexes, etc.
Network media - media that can be purchased in groups or sets, such as bus shelters, car bodies, subways, airports and train stations.