A digital billboard is a billboard

Billboard

Billboard is a weekly American magazine devoted to the music industry, and is one of the oldest trade magazines in the world. It maintains several internationally recognized music charts that track the most popular songs and albums in various categories on a weekly basis...

 that creates digital image

Digital image

A digital image is a numeric representation of a two-dimensional image. Depending on whether or not the image resolution is fixed, it may be of vector or raster type...

s that are changed by a computer every few seconds. Digital billboards are primarily used for advertising

Advertising

Advertising is a form of communication used to persuade an audience to take some action with respect to products, ideas, or services. Most commonly, the desired result is to drive consumer behavior with respect to a commercial offering, although political and ideological advertising is also common...

, but they can also serve public service

Public service announcement

A public service announcement or public service ad is a type of advertisement featured on television, radio, print or other media...

 purposes.

Safety concerns

There have been concerns regarding road safety when digital billboards are present. The Federal Highway Administration

Federal Highway Administration

The Federal Highway Administration is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two "programs," the Federal-aid Highway Program and the Federal Lands Highway Program...

(FHWA) conducted a study to review the effects of electronic billboards (EBBs) on crash rates. According to the FHWA, it appears that there is no effective technique or method appropriate for evaluating the safety effects of EBBs on driver attention or distraction.