I saw my father writing down the sales and status of his store by hand, so I created a management file that could be automated with Excel. I made it by searching Naver and making it by myself, but after watching this lecture, the magic happened where the code that was over 100 lines was reduced to 10 lines... It's really different from learning from YouTube, blogs, etc. step by step from the basics, so it's easy to understand and it's good to apply and use right away. I'm really grateful and recommend this lecture!