This lecture is so helpful, only focusing on the important points!! It was too difficult for me to read the book alone, and the blog? was simpler than the book, so there were parts that I didn't understand, so I followed the examples on the blog and looked up the parts I didn't understand in the book, but I couldn't concentrate and it was so frustrating to just read the textㅠㅠㅠ I'm so glad I found this lecture.. The PPT and lecture explanations are so good, and since the videos are divided into short segments, I can concentrate well (It's fun to finish each chapter..!) Thank you :)