Pay-per-click (PPC):-
Pay-per-click (PPC) search engines are those search engines that offer the marketing option called PPC to users. PPC is defined as the guaranteed placement of a small text "add" on the search results page for a specific keyword or keywords in return for a specified payment, but ONLY when a visitor clicks on that add. The advertiser pays nothing to appear on the results page; they only pay the amount they have agreed to (or bid for) when someone actually clicks/hits on their ad and is taken to their landing page; therefore, the term "pay per click".