Develop a complete backend application for user login and registration using Spring Boot with email verification in this comprehensive Java tutorial. Learn to set up a project using Spring Initializr, configure a PostgreSQL database, create user models, implement registration services, and integrate Spring Security. Explore how to test your implementation, handle email confirmations, and send verification links. Follow along with step-by-step instructions, from project bootstrapping to final testing, and gain practical experience in building secure user authentication systems with Java and Spring Boot.