On the page where you put adsense code - adsense matches the content and publish the relative ads to the place... Its simple. Hope it helps...
you place adsense ads on your site/blog, visitors visit your site and if they find those ads interesting, they will click on them. you get fraction of the revenue google gets from the advertisers.
adsense analyze the contents of your pages and show possible relevant ads on your page. when some on click on them you earn
Google AdSense delivers relevant text and image ads that are precisely targeted to your site and your site content. And when you add a Google search box to your site, AdSense delivers relevant text ads that are targeted to the Google search results pages generated by your visitors’ search request.
Google makes money when someone clicks on your ads and it gets split in between for you and them. This charges the advertiser though.
Google Adsense is A complete Programme. It provide the Publisher and advertiser information after you get the Adsense account, get adsense code and put into your site or blog, google appear always relevant ads on it and visitors search it your site/blog through Google or any other search engine. If your site / blog will be made clearly good healthy and informative content. Then user like it. If visitors not satisfiy it maybe click on your any one related ad and then you earn it form google adsense programme.
Adsense checks out your website's content and searches through the database of advertisements for something related to your site's content. After it finds relevant ads, it checks the highest bids from among the ads. These ads will be displayed first. So you'll get paid the most if someone clicks the ads with higher bids. That's how adsense actually works.