If you don't put the s in the filename, the server will simply ignore all of your include commands. Incidentally, our server is configured so that it will search for the file index.shtml if it can't find index.html . There is one main limitation you should be aware of when using server-side includes. Use server-side includes sparingly in your files, since they do slow them down, and place a heavier load on our server. This section explains how you actually put an include command in your document, and describes the tags and the environment variables you can use in your commands.
Commands take one or two tags.
3.2 Tags in includes As I explained above, the tags are the extra information you give to the server along with the command you want it to execute. I'll show you which tags go with which commands. There are four tags that we're interested in. The file tag is used when you want to give the server a file name. If you want it to include data from another file, you use this tag to let it know which one.