Webmaster in a Nutshell, Third Edition

Name

<IfModule>

Synopsis

                     <IfModule>
                     ...
                     </IfModule>
                  

A sectioning directive for specifying directives that apply if a given module has been compiled into the Apache server. For example:

<IfModule mod_cgi>
LoadModule mod_speling libexec/modspelling.so
</IfModule>

This directive is executed if Apache is compiled with the mod_cgi module. Note that you can place an exclamation mark in front of the module name to include such directives if a module is not included in the Apache server build.