Considering that not all students have the same ability, the lecture was created for beginners, so I was able to properly understand and study it, which was great. I attended a boot camp and know how to write code, but I lacked basic concepts about the Java language, so I took this lecture to build a solid foundation. Thanks to this, I was able to properly study the things I had vaguely known to follow the boot camp, and I am grateful that it helped me understand what is important in Java. I highly recommend this lecture to those who are having trouble like me. Mr. Kim Young-han, who kindly teaches with pictures when it is difficult to understand just through words... He is a god!