Even though I've been using JavaScript for quite a while, there were many times when I wondered if I was using it correctly, and since I only used the things I always used, I listened to the entire lecture with the mindset of studying it step by step, and it was a great help. While writing, I didn't wonder why... and I often copied and pasted things because I wanted to solve them quickly, but I was able to think about how it works and how it would be more efficient to write code in this way.