Got Milk? is an American advertising campaign encouraging the consumption of cow's milk, which was created by the advertising agency Goodby Silverstein & Partners for the California Milk Processor Board in 1993 and later licensed for use by milk processors and dairy farmers. It has been running since October 24, 1993. The campaign has been credited with greatly increasing milk sales in California though not nationwide.
Got Milk? is one of the most famous commodity brand and influential campaigns in the United States.
The advertisements would typically feature people in various situations involving dry or sticky foods and treats such as cookies. The person then would find himself in an uncomfortable situation due to a full mouth and no milk to wash it down. At the end of the commercial the character would look sadly to the camera and boldly displayed would be the words, "Got Milk?"
The first Got Milk? advert ran on October 29, 1993, and featured a hapless history buff (played by Sean Whalen) receiving a call to answer a radio station's $10,000 trivia question (voiced by Rob Paulsen), "Who shot Alexander Hamilton in that famous duel?" The man's apartment is shown to be a private museum to the duel, packed with artifacts. He answers the question correctly, but because his mouth is full of peanut butter and he has no milk to wash it down, his answer is unintelligible. The ad, directed by Hollywood directorMichael Bay, was at the top of the advertising industry's award circuit in 1994. From 1994 to 1995, fluid milk sales in the 12 regions totaled 23.3 billion pounds, and increased advertising expenditures amounted to $37.9 million. In 2002, the ad was named one of the ten best commercials of all time by a USA Today poll, and was run again nationwide that same year. It has since been featured in books on advertising and used in case studies.
The slogan "Got Milk?" was licensed to the National Milk Processor Board (MilkPEP) in 1995 to use on their celebrity print ads, which, since then, have included celebrities from the fields of sports, media and entertainment, as well as fictional characters from TV, video games, and film such as The Simpsons, Batman, Mario, The Powerpuff Girls posing in print advertisements sporting a "milk mustache," employing the slogan, "Where's your mustache?"
Former California Gov. Gray Davis expressed his dislike for one commercial and asked if there was a way to remove it from the air. It featured two children who refused to drink milk because their elderly next-door neighbor is energetic despite not drinking it. He is going to use his wheelbarrow when suddenly his arms snap off, because without his consumption of milk, his bones are weak and frail. The now-frightened children start imbibing the fluid. 
In 2006, the campaign went after a new demographic with a series of Spanish-language “Toma Leche?” or “Do you take/drink milk?” ads in which milk is touted as a "wonder tonic" with muscle and hair building qualities.
According to the Got Milk? website, the campaign has over 90% awareness in the US and the tag line has been licensed to dairy boards across the US since 1995. Got Milk? is a powerful property and has been licensed on a range of consumer goods includingBarbie dolls, Hot Wheels, baby and teen apparel, and kitchenware. The trademarked line has been widely parodied by groups championing a variety of causes. Many of these parodies use a lookalike rather than the actual persons used in the original Got Milk? adverts.
In 2008, the campaign capitalized on the poor economic condition of Americans and used financial adviser and talk show host, Suze Orman, in an effort to advertise milk as a smart and nutritious commodity to purchase.
The voice saying "Got Milk?" in the television commercials is that of veteran voiceover actor Denny Delk, however other anonymous narrators have said the question on occasion.
From : www.wikipedia.org