content directory of World Wide Web links owned by Netscape that is constructed and maintained by a community of volunteer editors. ODP uses a hierarchical ontology scheme for organizing site listings. Listings on a similar topic are grouped into categories, which can then include smaller categories. References: http://ezinearticles.com/?Advantages-and-Disadvantages-of-Affiliate-Marketing&id=299076 http://www.mso.net/Page-per-click-advertising---What-are-the-benefits- http://www.mso.net/Pay-per-click-advertising---What-are-the-drawbacks- Posted