By creating aliases for directories on your server, you can use them in your ColdFusion applications.
For example, if you want to refer to "/SPECIALDIR" in your CFML code, and you create a mapping for "/SPECIALDIR," it gets resolved to the actual name. Therefore, <CFINCLUDE Template="SPECIALDIR/index.cfm"> works at runtime.
Web server APIs supported by ColdFusion (NSAPI, ISAPI, Apache API, and WSAPI) perform document type mapping, which makes directory mapping in ColdFusion unnecessary. When a browser loads a file with the .cfm extension, the Web server recognizes that file type as a ColdFusion application page.
For details, see Create logical mappings.