It was a very good lecture that allowed me to understand the basic structure of Spring Security. I was able to see how the parts I vaguely knew were implemented at the code level and understand them, so I gained confidence that I could handle any issues related to Spring Security that might arise in the field. If I may give one tip to those who want to take this lecture, This lecture is an intermediate lecture. You should have at least a basic knowledge of Spring to understand it. I have seen some comments in the course reviews before taking the course that said the code has changed, but in this lecture, you should not place too much importance on each line of example code. It is more important to understand the overall concept and principles. If you cannot do something because of those few lines of changed code, it may not be suitable for this lecture level. As the lecture progressed, it focused a lot on parts that would not be used much in practice (like method security and real-time DB connection..ㅋㅋ), so I felt like it was a little bit longer, but it was okay when I thought of it as a review. !! I completed the course with great enjoyment until the end. I will keep an eye out for additional content in the future. Thank you for sharing such a great lecture!!