How To Make HTML Chunks?

example, i need to make an html/js/php sidebar, which can be edited independently of the page template. how?

thanks!

ok, chunks DO support html. i was confused by the documentation which says "Chunks are bits of static text", and none of the examples given are html. fortunately, this post explains that chunks can contain html, and can be used for menus and other reusable content.
http://codingpad.maryspad.com/2011/01/30/modx-revolution-for-complete-beginners-part-5-working-with-chunks/

Chunks can also contain JS code (in <script> tags). Basically they can contain anything you’d put on a web page except PHP code (which goes in snippets). When MODX sees a chunk tag, it just replaces it with the content of the named chunk (after checking to make sure the chunk has no PHP code in it).