Thanks to Kim Jeong-hwan's lecture, I was able to get a feel for what it means to write good code. I am a non-major and a student who has only been learning programming for a few months. I only heard people talk about good code and clean code, but I didn't really get a feel for what they were. Then, my mentor always recommended that I try coding with TDD. He said that it would help me make it a habit to track my work in very small units. So I looked for Kim Jeong-hwan's lecture. In addition to thinking in small units, I think I got a feel for what DRY code, which I had only heard about all the time, was like. Not only this lecture, but also the Node TDD development and the articles you wrote on your blog are really good. Thank you for providing such great lecture materials.