History of Advertising
In ancient times, the most common form of advertising was word of mouth, but commercial messages and political campaign displays have been found in the ruins of Pompeii.  Egyptians used papyrus to create sales messages and wall posters, while lost-and-found advertising on papyrus was common in Greece and Rome.  Wall or rock painting for commercial advertising is another display of an ancient media advertising form, which is still present now in many parts of Asia, Africa and South America.  As printing developed in the 15th & 16th century, advertising expanded to include handbills.  In the 17th century, advertisements started to appear in weekly newspapers in England.  As the economy was expanding during the 19th century, the need for advertising grew at the same pace.  In the U. S., classified ads became popular, filling pages of newspapers with small print messages, promoting all kinds of goods.  The success of this advertising format led to the growth of mail-order advertising, like the Sears Catalog.  In 1843, the first advertising agency was established by Volney Palmer in Philadelphia.  At first the agencies were just brokers for ad space in newspapers, but by the 20th century, advertising agencies started to take over responsibility for the content also.  The 1960s saw advertising turn into a modern more scientific approach where creativity was allowed to show, producing unexpected messages that made advertisements more tempting to the consumers' eyes.  The Volkswagen ad campaign featuring headlines like "Think Small" and "Lemon" brought in the era of modern advertising by promoting a "position" or "unique selling proposition" designed to associate each brand with a specific idea in the reader or viewers' mind.  The late 1980s and early 1990s saw the introduction of cable television and especially MTV.  Pioneering the concept of the music video, MTV brought a new type of advertising: the consumer tunes in for the advertisement, other than it being a byproduct or afterthought.  As cable (and later satellite) television became increasingly common, "specialty" channels began to come about, and eventually entire channels, like QVC and Home Shopping Network and Shop TV, devoted to advertising merchandise, where again the consumer tuned in for the ads.  Marketing through the internet opened new frontiers for advertisers and led to the "dot-com" boom of the 1990s.  Entire corporations operated only on advertising revenue, offering everything from coupons to free Internet access.  At the turn of the 21st century, the search engine Google revolutionized online advertising by emphasizing relevant, low-key ads intended to help, rather than overwhelm, users.  This has led to an excess of similar efforts and an increasing trend of interactive advertising.

Public service advertising
The same advertising techniques used to promote commercial goods & services can be used to inform, educate and motivate the public about non-commercial issues, like AIDS, political ideology, energy conservation, religious recruitment, & deforestation.  Advertising, in its non-commercial appearance, is a powerful educational tool capable of reaching and motivating large audiences.  "Advertising justifies its existence when used in the public interest - it is much too powerful a tool to use only for commercial purposes." - Attributed to Howard Gossage by David Ogilvy.  Public service advertising reached its height during World Wars I & II under the direction of several governments.

The impact of advertising
"Half the money I spend on advertising is wasted; the trouble is, I don't know which half." - John Wanamaker, father of modern advertising.  The impact of advertising has been a matter of considerable debate & many different claims have been made in different contexts.  During debates about the banning of cigarette advertising, a common claim from cigarette manufacturers was that cigarette advertising does not encourage people to smoke who would not otherwise.  The (eventually successful) opponents of advertising, on the other hand, claim that advertising does in fact increase consumption.  According to many media sources, the past experience & state of mind of the person subjected to advertising may determine the impact that advertisement has.  Children under the age of four may be unable to distinguish advertising from other TV programs, while the
ability to find the truthfulness of the message may not be developed
until the age of 8.

The future of advertising
With the dawn of the Internet have come many new advertising opportunities.  Pop-up, Flash, banner, advergaming, & email advertisements overflowing.  Every year greater sums are paid to get a commercial spot during the Super Bowl.  Companies try to make these commercials fairly entertaining that members of the public will actually want to watch them.  Another problem is people recording shows on DVR's (like TiVo).  These devices let users record the programs for later viewing, letting them fast forward through commercials.  Additionally, as more seasons or "Boxed Sets" come out of Television shows; fewer people are watching their shows on TV. But, the fact that these sets are sold, means the company will additionally get profits from the sales of these sets.  Especially since the rise of "entertaining" advertising, some people may like an advert enough that they wish to watch it later or show a friend.  In general, the advertising community has not yet made this easy, although some have used the Internet to widely distribute their adverts to anyone wanting to see or hear them.  Another meaningful trend to note for the future of advertising is the growing importance of niche or targeted ads.  Also brought about by the Internet & the theory of the Long Tail, advertisers will have an increasing ability to reach narrow audiences.  In the past, the most effective way to deliver a message was to blanket the largest mass market audience possible.  However, usage tracking, customer profiles and the growing popularity of niche content brought about by everything from blogs to social networking sites, provides advertisers with audiences that are smaller but much better defined, leading to ads that are more relevant to viewers & more effective for companies marketing products.