PPC refers to “Pay-Per-Click” advertising. Google AdWords is the leader in this category, providing advertisers the opportunity to pay their way onto the first page of their search results. PPC is a quick way to draw traffic to your site, but requires that you pay for every click. There are also concerns with click fraud.
Studies have found that the best ROI (return on investment) is organic Search Engine Optimization over Pay-Per-Click advertising.