hinclude.js

Tired of regenerating HTML pages from templates? Want more from Web caches?
HInclude makes one thing very easy; including other bits of HTML into your
Web page, using the browser.

HInclude is declarative client-side inclusion for the Web; it allows easy
composition of Web pages using the browser -- making your pages more modular,
more cacheable, and easier to maintain.

See the demo page for documentation and
examples.

If you're interested doing this with Web Components, see
Gustaf Nilsson Kotte's h-include.