Cost per click, which usually goes by the acronym of CPC, has two different meanings. For a search engine, the term cost per click means how much the search engine charges advertisers each time a visitor clicks on a sponsored link. Cost per click can also mean the total cost accrued by the advertiser when the ad is clicked on, from just listing the ad to the additional cost of the click-through on the part of the visitor. The CPC can vary for a search engine and for the advertiser, based on the popularity of the keywords, as well as the basic price that search engines charge. The more popular the keyword, the more expensive the cost per click for the advertiser and the more money the search engine makes.