Template parts vs. classic PHP templates
In classic WordPress themes, the header is defined in `header.php` and the footer in `footer.php` — editable only by code. In block themes, header and footer are template parts: visually editable in the Full Site Editor, stored as HTML files with Gutenberg block markup in the `/parts/` folder.
Creating and editing template parts
In the Full Site Editor (Appearance → Editor), existing template parts can be edited or new ones created. New parts are saved as HTML files in the theme. Template parts are included in templates via `<!-- wp:template-part {"slug":"header"} /-->`.
Template parts and anipage.io
anipage.io generates complete page content as Gutenberg block markup — including header- and footer-like sections. The export contains the page content (without theme template parts), which can be imported into existing WordPress themes without overwriting existing template parts.