What form of advertising can be experienced 24 hours a day, seven days a week, is not surrounded by editorial, programming or photographs, and can be targeted to reach specific audiences by neighborhood?

If you guessed outdoor, you're right. Outdoor advertising includes billboards, posters, airport ads, bus signs, mall posters transit shelters, stadium signs, bench advertising and more. It is estimated that there are more than 40 types of outdoor advertising, with billboards being the most widely recognized media.

Outdoor advertising also has another advantage, which is cost, opening the door for all advertisers -- small or large. According to the Outdoor Advertising Association of America, outdoor advertising is 80 percent less expensive than TV, 60 percent less expensive than newspapers and 50 percent less expensive than radio.

Unlike other advertising mediums, the audience viewing outdoor advertising is often bored, looking for something to read. This is what makes a moving billboard, like a bus, so interesting, compellingly creative and memorable. Creativity is the key element in outdoor advertising.

Outdoor is considered to be one of the oldest advertising mediums, yet technology has provided the opportunity to develop creative, eye-catching messages. High-impact billboards now include tri-vision signs which allow three advertising messages per location, 3-D images and even interactive billboards.

Another advantage that technology has provided is an incredible reduction in time to print ads.  Signs that previously took 40 hours to paint can now be printed in just two hours by printing on continuous inkjet printers.

Case studies prove the right message in the right place at the right time generates sales. Whether promoting new or existing products or personalities, both local and national companies know by dominating the medium and moving the message closer to the customers purchase decision, billboards work.

McDonalds uses billboards to direct hungry motorists off a highway to a specific location. Radio stations know the best place to remind listeners to switch stations is when they are in their cars. Car manufacturers realize there is no better way to reach their best prospects: drivers of cars and trucks.

Altoids created "Curiously Strong" brand awareness after implementing a campaign using alternative newspapers and a variety of outdoor advertising mediums. Outdoor generated an awareness of 76 percent, market share grew by a 5-to-1 margin vs. markets without advertising, and the brand's business grew by 31 percent to $18.7 million.