This document provides an overview of e-commerce. It defines e-commerce as the process of buying and selling online via electronic networks. A brief history is given starting in the 1970s with EDI and moving to widespread internet use in the 1990s and 2000s. The main categories of e-commerce are defined as business-to-consumer, business-to-business, consumer-to-consumer, and mobile commerce. Benefits to organizations include lower costs, improved customer relations, and a global reach, while consumers benefit from more options, cheaper prices, and instant delivery.