I thought I should watch it for a long time, but I ended up watching the lecture for about a month. I am currently working as a new employee in the development team, and when I read the existing code, I had a hard time interpreting it with the concepts I vaguely knew. While watching the lecture, I received a lot of help from the object-oriented approach rather than the existing approach. I will also complete the lecture on the TPC API that is coming soon!! Thank you. I will continue to study hard and receive help!! I think these people will be helped a lot! 1. I have taken Java lectures so far, but I don't understand how this is used. 2. I am working on a Java project, and I am reading, writing, and retrieving data... I am searching and progressing, but I don't understand why this is being used. 3. I have difficulty solving problems in an object-oriented manner when solving algorithm problems or studying on my own. (I was like this, and it helped me a lot!)