More often than not, we witness how TYPO3 editors put headings (H1, H2, H3,…) directly into the text area field of content elements "Text" or "Text with image." This means that they directly add the relevant HTML tags for headings here.
The formatting of these headers can of course be changed via a style sheet but this forfeits the possibilities provided by TYPO3.
Headings should always be added to the appropriate fields of the TYPO3 backend. The diverse orders (H1, H2, H3,…) can be assigned via the corresponding "Type" field.
Should a heading appear within a text area field, then the text must be split into two separate content elements and the heading is then added to the second element.
TYPO3 can only definitely recognise a header in this way. This has many advantages amongst others:
The text processing capabilities of TypoScript enable very sophisticated transformations of headings, for example expansion with any elements provided by TypoScript.
Headings can be shown automatically as anchor links [Content element "Menu/Sitemap", Menu type "Section index (pagecontent w/Index checked)"] or can be used in the other menu functions (