A wiki page can be just a few paragraphs of information, or it can hold a substantial document. As with any document, when it gets longer it helps to have some organization to the information. Using Header styles helps the author organize the information. Then using an automatically maintained Table of Contents allows the reader to quickly find the desired section of the document.
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Overview
The Table of Contents ("ToC") feature works in conjunction with the paragraph styles h1 through h6. This paragraph is in normal style, but the preceding one (the single word "Overview") has been marked with "h1" style. That style uses a larger default font size, and is automatically included in the ToC.
Note: there currently seems to be a quirk in the operation of the ToC button: it will not insert the ToC marker unless the page already has at least one paragraph styled as a header.
Not WYSIWYG
One of the weaknesses of the current ToC implementation is that it does not operate in a What-You-See-Is-What-You-Get ("WYSIWYG") fashion. That is, while you are in the edit mode for a page, you will not see the generated ToC - instead you will see only a text marker, something that looks like this:
[ TOC:Example Table of Contents:1 ]
When you Save the page, that marker will be converted into the filled in and formatted ToC.
References:
Table of Contents feature in wiki pages, beta@ #6948, Mark Fletcher, 2016-03-28
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