Highly recommended as an introductory Elasticsearch course. Pros. 1. Each lecture is around 10 minutes, making it easy to focus. 2. Code is provided, so you can finish the course quickly without typing. 3. It only covers the essentials without unnecessary content, allowing for a quick introduction. Books on the market felt like bibles and were boring, but after watching this lecture, I was able to quickly gain an overall understanding of Elasticsearch. It was also good to learn how it's used in practice. After watching this lecture, I think reading books will be easier to understand.