After learning coding at a national academy and getting a job in a hurry, I realized that I knew how to use Spring, but I didn't know any of its core principles or concepts... In this situation, I was recommended the instructor's lecture by a coworker, and I came to understand how the technologies I had been using in my field without thinking worked, and once I understood that, Spring became more interesting. Thank you for making such a great lecture, and I will follow the roadmap step by step...!