Sams Teach Yourself CGI in 24 Hours, Second Edition

Summary

SSI is a kind of shortcut around CGI. It provides you with some of the same dynamic page-building features as CGI, but it doesn’t allow nearly the level of interaction for your users. The number one advantage of SSI is that it can save you lots of work when you need to use the same snippet of HTML source code in many pages. You can create that snippet as a separate file and use SSI directives to load them into each page.