A table of contents is a list of titles and page numbers at all levels in a document, usually before articles. Word directories are divided into document directories, graphic directories, table directories and other types.

"Index" is like a clue, each clue corresponds to a complete piece of information, and the index plays an important role in a book or a document. The information conveyed by keywords allows us to find what we need quickly without blowing off the dust.

The difference between an index and a directory:

The so-called "table of contents" is a list of titles at all levels in a document, usually located after the title page of an article. The function of the table of contents is to facilitate readers to browse or locate the content of interest quickly, and to understand the outline structure of the article more easily.

The so-called "index" is a list with keywords as the retrieval object, usually before the back cover of the article. The function of the index is that readers can quickly locate the relevant positions of the text according to the corresponding keywords, such as names, places, concepts and terms, and obtain more detailed information of these keywords. In the middle school mathematics and physics textbooks we have used, there are usually indexes at the end, listing important concepts, definitions, theorems and so on. , so that we can quickly find out the details of these keywords.

The index focuses on finding the article you are looking for, and the table of contents focuses on showing the structure of the whole article.