yEd is a very powerful graph editor that is written entirely in the Java programming language. It can be used to quickly and effectively generate drawings and to apply automatic layouts to a range of different diagrams and networks. yEd is available as a free download with unrestricted functionality!
yEd makes full use of the yFiles library. This is a Java class library enabling the viewing, editing, optimizing, drawing, and animating of a wide range of diagrams, networks, and other graph-like structures.
yEd has been built using 100% lightweight Swing components. This allows it to run on any platform where a suitable Runtime Environment is available.