I need to use UML diagrams. Do you have any good information on this?
Hi, yes, you can take a look at this blog I 
draw.io – Three ways to improve your UML diagrams. It gives you ideas how to improve your UML diagrams in draw.io.
Fore more general info on draw.io for Confluence or Jira, please refer to our draw.io webpage.
And some more great blogposts! Blog - draw.io