This chapter introduces the basic concepts, connotations, and development status of e-commerce and financial payments. It begins with the definitions related to e-commerce and financial payments, including the concept of the third stream, which consists of information flow, capital flow, and logistics. The chapter then analyzes the collaboration among these three streams within e-commerce, explores the characteristics of e-commerce and financial payments, and discusses the relationship between them. Finally, it reviews the global development history of e-commerce and compares the current status at home and abroad. Overall, this chapter lays the theoretical foundation and background knowledge for the in-depth discussions in subsequent chapters.