Tools

Mind Map
Special kind of diagram with hierarchical tree structure. Mind maps begins with main idea at the center, which extends on other branches, which demonstrate any other subideas. Mind Map could be really useful for understanding some new concepts, analytics and synthesis of new information.

Mind Map Software

 * Freemind
 * Xmind

Concept Map Software

 * Visual Understanding Environment (VUE)
 * Lucid Chart Diagram