The document discusses electronic commerce (e-commerce) and its various models. It begins by defining e-commerce and describing how it allows trading of goods and services through electronic means like the internet. It then outlines several common e-commerce models including business-to-business (B2B), business-to-consumer (B2C), consumer-to-consumer (C2C) and others. The document also discusses important infrastructure considerations for e-commerce businesses, such as marketing, facilities, customer service, IT, fulfillment and more. Finally, it describes the evolution of electronic commerce through the commercialization of the internet and opportunities it provides consumers through access to a global marketplace.