First of all, thank you for providing such a great lecture for free. I am using Spring, but the concepts were always scattered in my head, but it was so much fun to understand the flow because you explained not only the core but also the reason for using the technology step by step with code. The lecture materials are simple but well organized, so I was able to review the parts I missed, and the answers to the questions on the Q&A bulletin board were so detailed that I was able to organize them again accurately. I took the lecture and it was so fun that I even paid for the package. I will study hard so that the instructor's knowledge can settle in my head :) Thank you again for sharing your knowledge and giving me a valuable learning experience ㅠㅠ!