The lecture content is good. I know how to use Linux, but I took both the basic and practical courses to organize it. One thing that is disappointing is that I am going to complete the basic course anyway, and if the content is good, listening to the practical course is a set procedure, but I think they advertise the practical course too much. The basic course is a course that you pay to listen to, not a free course. If there is someone who only listens to the basic course, they will think, "Did I buy this to listen to the advertisement?" because of the continuous advertising. The lecture content is good, but that is the only thing that was disappointing.