Learn to build a Java API using Spring Boot in this comprehensive tutorial. Explore HTTP methods, in-memory databases, N-tier architecture, dependency injection, and interface programming. Discover how to structure applications, autowire beans, and run .jar files for server deployment. Practice using Postman REST Client for testing. Follow along to create a full-stack application, with source code and additional resources provided. Gain hands-on experience implementing GET, POST, PUT, and DELETE operations while building a robust backend system.