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Global Variables
In this section you can define custom data that you would like to be available globally in any Template. This is in addition to the standard Global Variables that are already available.
You could create a Global Variable for any number of purposes. One idea would be for a piece of copyright text that would be included on every page. By making it a Global Variable you can change it in one place and immediately see the effects everywhere.
Global Variables can contain text, HTML, javascript, etc. but cannot contain PHP code or ExpressionEngine tags that you wish to have parsed.