E-commerce involves the exchange of goods and services over electronic systems like the internet. It requires products or services to sell, a way to accept orders and payments, fulfillment of orders, and customer service. There are four main categories of e-commerce: business to business, business to consumer, consumer to consumer, and consumer to business. Key drivers include technology, policies, skills, economics, and competition. Benefits include lower costs, larger markets, and improved customer interactions, while limitations relate to security, access, standards, and lack of human interaction.