Fan Fan usually refers to the text of the content and style of the instruction before the text of the book. These contents may include structure, content, chapter arrangement, use of terms and symbols, etc. The purpose of examples is to help readers better understand and use books.
General principles usually refer to universally applicable rules or laws and are the basis for formulating other rules. These general principles are usually based on certain principles, laws, practices or other standards. General principles are usually used to describe the scope of application of making rules and help people understand how to abide by and apply these rules.
Generally speaking, each example mainly focuses on the content and style of books to help readers better understand and use books; General principles focus more on the basis and scope of application of rules to help people understand and abide by these rules.