Soon after the advent of internet, it was realized that the website real estate (or the space on websites) had commercial value in the advertising world. The simple reason behind this was the soaring popularity of internet and the increasing number of eyeballs received by various websites. Thus, internet advertising (or online advertising) came into being. Today, internet advertising is treated as one of the most effective and most economical means of advertising. In fact, a lot of businesses, especially small businesses, use only this (affordable) medium for advertising their products and services. As technology progressed, so did the online advertising methodologies. Graphics based banner Ads and text Ads got their due recognition and were used quite extensively for online advertising. Even now banner advertising is one of the most popular forms of online advertising.

However, the real breakthrough in online advertising came with Google AdSense advertising program. This program helped in connecting advertisers to several website owners who were ready to offer advertising space on their websites. Through Google AdSense program, the advertisements were floated on the websites that had some relevance to the products or services offered by the advertiser. This type of advertising is also called targeted advertising since the Ads are served only to the interested audience and not just anyone or everyone. Soon, Google AdSense became a very effective form of targeted advertising. On Google AdSense program, webmasters are paid on per-click and per-thousand-Ads-displayed basis. And the advertisers can control the amount of money they wish to spend on advertising through Google Adwords program that works in conjunction with the AdSense program.

Google AdSense program has caught the fancy of a lot of advertisers and webmasters and its popularity continues to soar everyday. Until another, better advertising program comes into being; Google will continue to hold its place at the core of online advertising.