When an advertisement is made online on a web site that is different than the site where the product is sold, or where there is an advertisement paid for on the search engine, the common method of payment is one that charges a rate per click which accrues over a set amount of time. This is called Pay Per Click (PPC).
The pay per click is a way of gaining more customers other than what may be gathered through simple organic visits. Search engine advertising is probably the most popular form of PPC which sees advertisers bid for space on the sponsored links list. Every time a user searches for a term that has been linked to the search engine of the web site the site will come up and the choice will be available for the user to click on the link.