mind mapping and brainstorming tool.
Best Tools For Visual Modeling
Browse 9 + Visual Modeling Tools

Xmind

Mindomo
Mind Mapping for thinking organization or structuring
draw.io
Diagram creation for modeling systems

d3
Bring data to life with SVG, Canvas and HTML. đđđ

graphviz
Open source graph visualization software

Yed Graph Editor
High-quality diagrams made easy

Dia Diagram Editor
Free drawing software for Windows, Mac OS X, and Linux

Bizagi Modeler
Diagram creation for modeling systems

Web Sequence Diagrams
Diagram creation