I had been learning only how to use Spring technology, so I found myself unable to directly explain Spring's principles in words. By intensively studying this short lecture of about 3 hours in one day, I gained insights that allowed me to explain component scanning, DI, and other concepts I had known about in more concrete terms. Additionally, I was able to learn about annotations and reflection, which I had never quite grasped before, and understand how these are utilized in Spring, making this a very satisfying lecture. I believe the content I learned from this lecture will be tremendously helpful when acquiring advanced Spring-related technologies in the future.