B2c, b2b, b2g: non-merchant companies: those that arrange for the purchase and sale of goods without ever owning or taking title to those goods, sell services provided by others, eg. Auctions, clearinghouses, exchanges: ecommerce merchant companies, 1. Those that sell directly to consumers: business to consumer (b2c) sales between a supplied and a retail customer - web storefront: where customers enter and manage their order, 2. Those that sell to companies: business to business (b2b) refers to sales between companies, 3. Knowledge of price elasticity: losing-bidder auction prices, price experimentation, more accurate information obtained directly from customer. Factories, machines, manufacturing equipment: human capital: the investment in human knowledge and skills for future profit, social capital: investment in social relations with the expectation of returns in the marketplace, social capital adds value in four ways, 1. Personal reinforcement: how is social networking enables by is/it, 1. Reduction in the trade of off richness and reach: 3.