Understanding Include Files

Include files are individual files that can be repeatedly called into different pages (for example, ColdFusion, PHP, .NET, or JSP pages). A blessing to Web designers, include files not only allow a site to be modular (various easily interchangeable pieces), but more importantly, they also reduce maintenance time. An example of an include file might be the footer text of a site. Instead of placing the text in every page, a designer might include one line of code in every page that calls that footer text, which is in only one file. Then, when the footer needs to be edited, the designer edits only one page.

To use include files, all a designer needs is to host a site on a server that offers server-side processing, such as Microsoft (.NET pages), Apache HTTP Server (SHTML pages), Adobe ColdFusion server (CFM pages), JSP server (JSP pages), or an open-source server that runs PHP pages. Following are examples of code that are used to include files into other files: