Pay Per Click or PPC

Serves up your website in search results and also optionally on other peoples's sites (See "Google Adsense") according to specific keywords you bid for. You are charged when someone clicks on your advertisement.

PPC is effective inasmuch as it gives your site faster Page 1 presence and wider prominence through the "Content Network" (Adsense) than through organic SEO.  You are ranked in results according to how much you are prepared to bid.  

Paradoxically, however, to do well in PPC (cheaper ads, more impressions), you need to optimise your site in the same way as you would for Organic Search.

I have noticed that the presence of an ad often reinforces the click-through in the organic search results.  Take away the PPC ad and the organic clicks suffer too.

Like advertising in the real-world, if you do not know what you are doing, PPC is also a fine way to lose a lot of money with no results.  You really need to take advice.