Pay per click better known as PPC Advertising, is as the name suggests an Online Advertising model. Traffic for any website can be generated by the website itself, or by taking help of other websites. This model is based on taking external assistance from other websites. A website makes certain advertisements for its business; it then negotiates with other websites to host its ad. This arrangement works on the understanding that the advertisers pay the hosting service when the ad is clicked.
These advertisements can be hosted on search engines or on content based websites. For search engine's advertisers typically have to bid for keywords relevant to their target market. Content sites commonly charge a fixed price per click rather than use a bidding system.