Because the runtime is short, I listened to it all at once as if I was listening to a liberal arts lecture :) I knew about asynchrony and used it when working on projects, but I thought I didn't understand it properly, and I think this lecture explained those parts well from the basics. If there is anyone who is studying the basics of JavaScript and wants to learn about asynchrony properly, I think it would be good to take this lecture. Additionally, it would be good if there was a follow-up lecture that gave a simple example of how to use asynchronous programs in practice. The instructor's voice was also very good, and I listened with satisfaction. Thank you.