This document provides an overview of electronic commerce and its key concepts. It discusses the basic elements of e-commerce including business-to-consumer, business-to-business transactions. The document also outlines the advantages of e-commerce such as increased sales and reduced costs. Some challenges of e-commerce are that some business processes are difficult to implement electronically and return on investment can be hard to measure. The origins and growth of the internet and world wide web are summarized as enabling technologies for e-commerce.