Google uses its Internet search technology to serve advertisements based on website content, the user's geographical location, and other factors. Those wanting to advertise with Google's targeted advertisement system may enroll through Google AdWords. AdSense has become a popular company in creating and placing banner advertisements on a website, because the advertisements are less intrusive than most banners, and the content of the advertisements is often relevant to the website.
Many websites use AdSense to monetize their content; it is the most popular advertising network.AdSense has been particularly important for delivering advertising revenue to small websites that do not have the resources for developing advertising sales programs and sales people to generate revenue with. To fill a website with advertisements that are relevant to the topics discussed, webmasters place a brief HTML code on the websites' pages. Websites that are content-rich have been very successful with this advertising program, as noted in a number of publisher case studies on the AdSense website. AdSense publishers may only place three ad units per page.
Some webmasters put significant effort into maximizing their own AdSense income. They do this in three ways:
- They use a wide range of traffic-generating techniques, including but not limited to online advertising.
- They build valuable content on their websites that attracts AdSense advertisements, which pay out the most when they are clicked.
- They use text content on their websites that encourages visitors to click on advertisements. Note that Google prohibits webmasters from using phrases like "Click on my AdSense ads" to increase click rates. The phrases accepted are "Sponsored Links" and "Advertisements".
- The webmaster inserts the AdSense JavaScript code into a webpage.
- Each time this page is visited, the JavaScript code uses inlined JSON to display content fetched from Google's servers.
- For contextual advertisements, Google's servers use a cache of the page to determine a set of high-value keywords. If keywords have been cached already, advertisements are served for those keywords based on the AdWords bidding system. (More details are described in the AdSense patent.)
- For site-targeted advertisements, the advertiser chooses the page(s) on which to display advertisements, and pays based on cost per mille (CPM), or the price advertisers choose to pay for every thousand advertisements displayed.[16][17]
- For referrals, Google adds money to the advertiser's account when visitors either download the referred software or subscribe to the referred service.[18] The referral program was retired in August 2008.[19]
- Search advertisements are added to the list of results after the visitor performs a search.
- Because the JavaScript is sent to the Web browser when the page is requested, it is possible for other website owners to copy the JavaScript code into their own webpages. To protect against this type of fraud, AdSense customers can specify the pages on which advertisements should be shown. AdSense then ignores clicks from pages other than those specified.
reposted and non righted post, source: google adsense