Advertising is marketing communication, usually with the end goal of persuading a consumer to act. It utilizes many creative fields to effectively create ads for traditional distribution (such as print, television, and radio broadcast) and new media (such as mobile, online, and social media).
Advertising Agencies can handle all aspects of campaign oversight (full-service); specialize in a single, well-defined aspect of the process (such as a creative boutique); serve one distribution channel (as in an SEO agency); or focus on one industry exclusively (like healthcare, or automotive advertising).