Server-Side Include - a program that
operates on the server computer versus on that of the viewer. Having programs
rest on a server allow dynamic content generation and manipulation while
maintaining security of vital information.
Many websites use server side includes for common page
elements such as navigation or design. Static pages (.htm or .html) can
not use servers side inclued unless you change the file paths (to .shtml
or .shtm) or reconfigure how the server parses the pages.
If you reconstruct file paths you risk loosing a portion
of your link popularity. One of the easier ways to use server side includes
on pages with the wrong filepath type is by altering the .htaccess file.
Many sites use server side includes to place the date
and other dynamic user driven elements on the page.