I was listening to Spring Core Principles - Basics and then moved on to Spring Introduction. I think it was a good idea to listen to it without skipping the introduction. In addition to the concept of Spring, the concept of actual business services is also grasped, so it would be best if you listen to the Java-Spring lecture as a backend development study for employment. Even if you are not a Java-Spring developer, since the business model is minimized and simplified and created little by little with the concept of a toy project, I recommend this lecture to those who really want to get a job or those who have studied a lot of theory but are unfamiliar with actual projects. I am getting a lot of help through the lectures you have prepared. Thank you so much for providing such high-quality lectures online at a reasonable price. I would also like to thank Kim Young-han and the many supporters who work hard.