Pay-per-click (PPC), also known as cost per click (CPC), is an internet advertising model used to direct traffic to websites, in which an advertiser pays a publisher (typically a website owner or a network of websites) when the ad is clicked.
Pay-per-click is commonly associated with first-tier search engines (such as Google AdWords and Microsoft Bing Ads). With search engines, advertisers typically bid on keyword phrases relevant to their target market. In contrast, content sites commonly charge a fixed price per click rather than use a bidding system. PPC "display" advertisements, also known as "banner" ads, are shown on web sites with related content that have agreed to show ads and are typically not pay-per-click advertising. Social networks such as Facebook and Twitter have also adopted pay-per-click as one of their advertising models.
However, websites can offer PPC ads. Websites that utilize PPC ads will display an advertisement when a keyword query matches an advertiser's keyword list, or when a content site displays relevant content. Such advertisements are called sponsored links or sponsored ads, and appear adjacent to, above, or beneath organic results on search engine results pages, or anywhere a web developer chooses on a content site.
The PPC advertising model is open to abuse through click fraud,[ althoughGoogle and others have implemented automated systems to guard against abusive clicks by competitors or corrupt web developers.