A book chapter in research is a specific, usually titled, section of a book that contains research on a particular topic. Book chapters are usually written by one or more scholars who have expertise in the topic, and they are typically peer-reviewed by other scholars before being published.
Book chapters can be a great way to get exposure to new ideas and research in your field. They can also be a good way to learn about a specific topic if you don't have time to read an entire book. However, because chapters are usually written by different authors, they can be inconsistent in quality and style.
If you're looking for specific information on a topic, it's often best to consult a database of journal articles or a specific book on the topic. However, if you're just looking for a general overview of a topic, book chapters can be a great place to start.