I could understand why the martial artists search for secrets and even stake their families' fates on one secret. Every word you say is unfathomably profound. I am so grateful that you teach such profound concepts in an easy way. After studying object-oriented for about a year and a half, I started studying function-oriented, so what is function-oriented? I studied for 10 months and a half, but it felt like a cloud in the sky, but I found the clue to its true meaning here. Even though I have not even listened to half of the lecture, I am learning a lot from the depth of the content. Above all, it is fun. Thank you.