What are Server Side Includes?

Note: For information about the recent migration to Webserve, see About the IU central web server migration or the IU Webmaster's Migration Information page.

Server Side Includes (SSI), a feature of certain web page servers, allow you to include a common function in a number of different web pages. Using SSI, you can quickly and easily insert or update design elements such as headers, footers, tables, or frames across many web pages.

A Server Side Include file works almost like an HTML file. The only difference is that with an SSI file, the server must look at each line in the file for SSI commands. If the server finds a command, it tries to execute it. The output of the SSI command will appear in the HTML text as if it were typed at the location of the SSI command. SSI files commonly have the extension .shtml at the end of their filename.

Note: Not all web servers support SSI, and due to the increased load that SSI places on the server in some systems, some administrators disable it even when it is included as part of the server software.

SSI is disabled on Mypage at Indiana University. It is available on Webserve, but the #exec command is disabled.

Also see:

• How do I make server-side imagemaps?
• On IU's web server, how can I use forms and CGI applications?