With the advent of the ad server, marketing through the Internet opened new frontiers for advertisers and contributed to the "dot-com" boom of the 1990s. Entire corporations operated solely on advertising revenue, offering everything from coupons to free Internet access. At the turn of the 21st century, a number of websites including the search engine Google, started a change in online advertising by emphasizing contextually relevant, unobtrusive ads intended to help, rather than inundate, users. This has led to a plethora of similar efforts and an increasing trend of interactive advertising.
The share of advertising spending relative to GDP has changed little across large changes in media. For example, in the US in 1925, the main advertising media were newspapers, magazines, signs onstreetcars, and outdoor posters. Advertising spending as a share of GDP was about 2.9 percent. By 1998, television and radio had become major advertising media. Nonetheless, advertising spending as a share of GDP was slightly lower—about 2.4 percent.
The computer completely changed the industry again in the late 1990s. Designers digitally completed their illustration and design composition. Many newspapers now use direct-to-plate technology, so ad layouts are only printed for proofing purposes, if at all.