Search engine Spock.com raises privacy issues by trying to index the world's population.
Yahoo Search Marketing was previously known as Overture and Go To. It was taken over by Yahoo in 2003. Yahoo Search Marketing is a key player in pay per click advertising marketing. Not only it provides search results to Yahoo but also MSN, Infospace, Netscape, Altavista and Lycos.
That means a lot of users and lot of potential traffic.
The basic principles of PPC campaign are good keyword strategy and the process to convert your visitors into customers. Campaigns need to be placed so that you end up earning more than you bid.