The difficulty level needs to be adjusted. Beginners shouldn't see this course as their main course. I took Inflearn's lectures as positively as possible. Because most of them are free courses and most of them are new to online lectures. And I didn't think of them as my main learning, but as a sub-learning tool, so I took them lightly. However, this course is a paid course with a textbook, but it doesn't take into account the listeners. If you understand this course in one go, I don't think you need to take this course. The course itself is quite fast-paced and really crazy. "You know this and that, right?" So I watched it twice or more to understand, and if I really didn't understand, I often had to check the related references on the Internet again to understand. Because of that, I think the difficulty level is higher. I think it's suitable for beginners or higher. In conclusion, it's an expensive course that requires you to buy a textbook. It's true that the lecturer is high-level. But from the perspective of the viewer, it didn't feel like it was at the beginner level indicated, and it just felt like it was progressing mindlessly.