I was studying Spring Boot documentation on my own and happened to find out about Baek Ki-seon on YouTube... I found out about Baek Ki-seon's lectures on Inflearn and am taking several of them... It's really good because he explains the concepts in this way. After I finish the lectures I paid for, I want to take the Spring Security class too... The lectures are so good that I'm recommending them to all my coworkers... Thank you for creating such a great lecture.