Freeplane is a mind mapping app that gives you the perfect vehicle for keeping your brainstorming session ideas organized and saved.

You can use it for mind mapping and analyzing the information contained in those mind maps. Freeplane runs on any operating system that has a current version of Java installed.

Freeplane's interface has a lot going on, but it is intuitive allowing you to insert various elements into the mind map like a question or exclamation mark, stars, light bulbs, information signs, numbers, bombs, and more. It provides templates to aid in mind map creation and supports multiple tabs, allowing you to work with multiple projects simultaneously.

Features:

Note taking with freely positionable, unconnected nodes (like post-it’s);
Ordering ideas (nodes) into a hierarchy connected by lines (edges);
Classifying nodes with metadata (attributes) and style types (system styles, user defined styles, level styles);
Grouping nodes with visual containers (clouds) and accolade (summary node);
Connecting nodes with dynamic links, free lines (connectors) and labels
Automatically styling nodes (with a bubble, color, edge type, etc.) according to hierarchical level and content (conditional styles, automatic edge color, level styles)
Structuring nodes concerning content (text, scientific formula, calculation, icon, image, and hyperlink) and presentation area (core, details, notes, attributes, images, and tooltip)
Changing views by hiding content (folding branches, filtering, a roll-up of details and hiding extensions in tooltip), finding, scrolling and navigating
Tasking with calendar and reminders
Password protecting of whole map and of individual nodes with DES encryption
Ease of use with inline- and dialog editors, object-oriented main menu context menu’s, multi-language support, spell checker, properties panel drag& drop functionality, hotkeys, options for batch execution, publishing, sharing and selectable preferences
Approximate Search (similarity search) which allows to find search terms in a text, even if there is no exact match (e.g. "setup" = "set up" or "flie" = "file")
Support for LaTeX formulae underneath/in nodes
Easy extension of functionality with add-ons and home made scripts
Integration with Docear academic literature suite
Extensive support through Wiki and Forum; and tutorial and documentation in the form of a mind map