HTML the markup vocabulary itself doesn't have these, which makes sense when seeing HTML as an SGML application inheriting all what SGML had to offer for transclusion using entities, and quite powerful means for content-oriented applications such as using markdown (or other custom syntax), building tables of contents/site maps, search context snippet and other summary generation, type-checked user and third-party content inclusion, etc. See [1] to get a flavor for including a shared header/menu and footer on multiple pages.

[1]: http://sgmljs.net/docs/producing-html-tutorial/producing-htm...