It explains everything in detail, and in line with the saying that it is an exit for culture and an entrance for a job, it also mixes in interesting stories about history, the web, and studies other than HTML, making it easy to listen to, and it also provides guidance on the path after the lecture. In addition, the appendix also shows simple and effective ways to apply functions externally, which is good. If you have even a little interest in the web, it is a good lecture worth listening to.