start a heading. Render it with view.

Customize how the heading looks. The visual hierarchy should go Top -> Tagline -> Subhead -> Small.

heading [ text "Hello, World!" ]
    |> withVisualLevel Top
    |> view

Customize the document level of the heading. For accessibility reasons, you should have exactly one H1, and only increase the level by one. You can use a tool like axe to check this.

heading [ text "Hello, World!" ]
    |> withDocumentLevel H1
    |> view

render a Heading to Html. See the other docs in this module for customizations.