NETSCORE - MEDIA METRIX is a revolutionary Internet traffic measurement service based on the largest opt-in network of more than 1.2 million active Internet users in the US for the top 10,000 web domains. Key Traffic Measurements, Audience Demographics and actual Internet Purchasing Transactions are captured for analysis. Statistical methodologies approved for the Internet, accurately project this large sample to the Internet Universe for critical business marketing and financial decisions, efficient media buys, and insightful competitive analysis.