Structure with the help of multi-level headings
One of the main tools for structuring documents is the use of headings. On a visual level, headings are usually marked with a larger font size or a bolder font style. However, the visual appearance on its own is not enough.
For Accessibility the headings are additionally marked with <H1>, <H2>, <H3>, <H4>, <H5> or <H6> tags in the PDF format. The numbers in those heading tags reflect a hierarchy from the highest level <H1> to the lowest level <H6>. This hierarchy allows content parts to be nested and assigned to each other.
The assignment of these tags gives the header texts a semantic meaning. Thus, assistive technology (AT) automatically recognises which heading and heading level it is.
This not only helps AT users to better understand the content, but also provides them with an important navigation tool. 67.5% of screenreader users have stated, according to a WebAIM survey, that headings are their most important tool for finding content.
The heading tags can already be assigned using the authoring software. See also: