clipped from: bignosebird.com   
WHAT IS SSI?
You may have noticed as you browse this site, that our pages end with the shtml extension instead of the more familiar html or htm. This is because we use Server Side Includes (SSI). Used properly, the SSI can help make your pages more responsive and can even help make maintaining your site an easier task.

SSI also seems to be one of the better kept secrets around. In any web related book, they seem to get about 1 page for every 200 pages on CGI and FORMS.

THE SSI TUTORIALS & REFERENCE PAGES
Here they are, a collection of information on SSI that you will surely want to bookmark this page for.

  • Performance Considerations. Nothing good in life is free (usually), and so it is the same for SSI. Here is some food for thought on server performance.


  • The INCLUDE Directive. Discover how to make your pages very simple to maintain. Use this directive to merge text files in with your pages. Great for those side bar type menus.