Usage
Clicking the 
button or inserting the Gliffy macro (described below) will create a new diagram. Each diagram has two links below it: 'Full Size' and 'Edit Diagram'. Clicking 'Edit Diagram' will bring up the Gliffy web-based editor where you can create and modify your diagram. When you're done, click 'Back to Wiki"'; your diagram will be saved and you'll be sent back to the original wiki page.
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The Gliffy editor also lets you export your diagram as SVG, PNG or JPG if you need to use it outside of the wikis.
Gliffy Plugin Video
Gliffy Macro
The Gliffy Macro is automatically created and inserted into your page when you click 'Add Diagram.' However, you can also insert it manually to reference a diagram attached to another page:
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