Backend development involves understanding the differences between backend and frontend, choosing appropriate programming languages (Java, Python, JS, Go, Rust, C#), working with various types of databases (SQL, NoSQL, NewSQL), learning about different API types (REST, GraphQL, gRPC, SOAP) and authentication methods (JWT, OAuth2, API keys). Additionally, it includes knowledge of server hosting services, containerization, server setup, and DevOps practices including CI/CD pipelines, IaC, and monitoring tools.