I am leaving a review hoping that all junior developers and all developers who are preparing for employment will be encouraged. I have been a developer for over 7 years and am currently a team leader at my company. While listening to this lecture, I realized that I still have a lot to learn and I am so happy to have had the opportunity to listen to this lecture. So far, while working with Spring, I have occasionally analyzed the functions provided by Spring and processed and used the interfaces. If you don't know the basic concepts of Java here, you may give up implementing the function or have sleepless nights after deployment because you are afraid. I thought I knew it until I listened to the lecture, but I realized that I didn't know it properly. The point is this. Developers like me who don't understand things properly somehow get jobs and work. So don't give up while listening to the lecture and keep fighting until the end. Finally, I would like to thank Young-han for providing this lecture, which will help me become a developer who can take a step forward. Thank you.