This document discusses e-commerce and defines its key types: business-to-business, business-to-consumer, business-to-government, and customer-to-customer. It also covers encryption, electronic certificates, and protocols used in e-commerce. The document notes that e-commerce is governed by the UN Model Law on Electronic Commerce and follows a functional equivalent approach, technology neutrality, data protection, and non-discrimination. It provides steps for building an e-commerce application using Ruby on Rails including running a web server and connecting to a MySQL database.