Lucidchart is a diagramming software that’s available online. Users can collaborate on drawing, revising, and sharing charts and diagrams. LucidChart is used for creating flowcharts, diagrams, network maps and diagrams, graphic organizers, mind maps, webs, UML diagrams, and much more. It is produced by Lucid Software Inc., based in Utah, United States. It was first released in December 2008.

You can sign up and use some features for free. With the free acoount you can edit your 3 most recently created documents and the rest are view only.