It was great that I could learn the content I really wanted to know in just one hour. The explanation was also great, but I thought people would normally use the Windows operating system, but since you wrote it in the MAC operating system, it would have been perfect if you had attached a little bit of PuTTY usage instructions for the part where you create an EC2 instance. (In fact, if you search it on Google, it only takes 5 minutes.) Hahaha. Still, it was great that you were able to watch this kind of quality lecture in a free lecture :) Thank you~~