Pay per click (PPC) advertising is the most common form of advertising revenue for web publishers. It is centered around paying the website publisher money each time someone clicks on the ad. Advertisers usually bid on keywords, with some keywords much more expensive than others. Therefore, the rate paid per click on an ad varies per ad and niche.

Some people build websites around high valued keywords in Google Adsense in order to make more money. What they have to realize is many of these keywords are high bid because there is low demand for clicks and because of the competitiveness of the industry. So you might get more money per click, but so few people click on them and/or visit these kind of websites, your overall profits will be less.

For example mesothelioma is a very high priced keyword in many PPC networks. If you build a website centered around mesothelioma you probably will have a hard time even getting a lot of traffic to your website because there will be so many websites out there trying to take advantage of this high bid keyword. To make matters worse there will be few people even looking at these types of websites in the first place, because not too many people are suffering or know anyone suffering from mesothelioma.

I recommend Google adsense as the best PPC advertiser due to their high click through rate and high payout rate per click. I usually earn around 30 cents on average per click.