CFG files normally refer to configuration files for applications or your operating system. If you have Microsoft Office installed on a Windows machine, these may be referred to as "Microsoft Office Outlook Configuration Files", though other applications use configuration files with the .cfg file extension.

Configuration files contain information useful to the execution of various applications, and may contain:

* Document printing options
* Recently-used file locations
* Selected color scheme
* Toolbar buttons to display

or virtually any other type of information you can imagine.

Configuration files are inherent to the application or operating system component using the file, and thus have no standard format. Some configuration files may appear like so in Notepad or another text editor:

Item1=Choice
Item2=Choice

OR:

<?xml version ="1.0"?>
<configuration>
	<item>
		Choice
	</item>
	<item2>
		Choice
	</item2>
</configuration>

OR they can be other types of text files, or they may contain binary data unreadable in programs such as Notepad.

Normally, these files should not be edited unless you read information in a particular application's documentation about how to modify them to change program settings.

Windows users: NOTE that unless you have configured your computer with the file extension viewing tweak, it is possible that a filename that looks like it ends with ".cfg", especially one attached to an e-mail message, actually has a hidden OTHER extension, meaning that if you double-click the file, it may actually run a computer virus!

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