Advertising
Advertising is an audio or visual form of marketing communication that employs an openly sponsored, non-personal message to promote or sell a product, service or idea. Sponsors of advertising are typically businesses wishing to promote their products or services. Advertising is differentiated from public relations in that an advertiser pays for and has control over the message. It differs from personal selling in that the message is non-personal, i.e., not directed to a particular individual. Advertising is communicated through various mass media, including traditional media such as newspapers, magazines, television, radio, outdoor advertising or direct mail; and new media such as search results, blogs, social media, websites or text messages. The actual presentation of the message in a medium is referred to as an advertisement or "ad" for short.
Advertising
There are a lot of great technicians in advertising. And unfortunately they talk the best game. They know all the rules. They can tell you that people in an ad will get you greater readership. They can tell you that a sentence should be this short or that long. They can tell you that body copy should be broken up for easier reading. They can give you fact after fact after fact. They are the scientists of advertising. But there's one little rub. Advertising is fundamentally persuasion and persuasion happens to be not a science, but an art.
William Bernbach, Letter (5/15/47) as quoted in Shaun Usher, Letters of Note: Volume 2: An Eclectic Collection of Correspondence Deserving of a Wider Audience (2016), p.190