Pay Per Click Advertising
Pay Per Click advertising (PPC advertising) is a type of search engine marketing where advertisers pay a pre-determined amount every time their ad is clicked on by a potential customer (otherwise known as a click thru).
Pay Per Click management services work on the basis that you only pay for your advertising when someone clicks on your advertisement. Typically, to determine the price advertisers will ‘pay per click’ the search engines use an auction model.
There are other factors that can determine your cost per click but generally it's decided on by the number of advertisers (competitors) for any given keyword. The person who pays the most appears highest in the paid placement search results. It is common that content sites charge a fixed price per click instead of using the auction model.
Pay Per Click advertising can be a great way to get traffic to your site if managed properly however, poor management could end up costing you a fortune with no results at all.
On the bright side it can give you great placement and generate traffic immediately. On the dark side you may not want to have your listing appearing in the shadier areas of the internet which helps generate traffic to your site, but may not be the type of client you are looking for.