Notes Icon. How to implement?

I have noticed on some example programs and a few from the free examples site, that they contain a Notes Icon in the Navigator side of the IDE just like methods, properties, etc. The notes, when clicked on, shows a screen of readme text about the program just like a method or action event would. Is this a special Xojo feature? I cannot duplicate it. I dragged a text file onto the navigator and it performed just like I wanted, but the icon was not the cute yellow, “Notes icon”.
Maybe this is a third party feature? How can I duplicate this?

Top menu

Insert -> Note

then just paste your text

Thank you! There are so many options there I never got around to checking them all out. I appreciate your help!