What is Mind Mapping?

Quoting Wikipedia:

A mind map is a diagram used to represent words, ideas, tasks, or other items linked to and arranged radially around a central key word or idea. It is used to generate, visualize, structure, and classify ideas, and as an aid in study, organization, problem solving, decision making, and writing.

An illustration of a Mind Map on Happiness (Source: http://www.mind-mapping.co.uk)

Why Mind mapping is essential?

The elements of a mind map are arranged intuitively according to the flow of thoughts, and are classified into nodes, branches, or areas, with the goal of representing connections between portions of information. Advantages of Mind Maps are simplicity and the easy graphical representation enables easy understanding and memory retention.

Mind maps are perfect for brain storming as it involves presentation of ideas in a radial, graphical, non-linear manner. Though the branches of a mind map represent hierarchical tree structures, their radial arrangement disrupts the prioritizing of concepts typically associated with hierarchies presented with more linear visual cues. This orientation towards brainstorming encourages users to enumerate and connect concepts without a tendency to begin within a particular conceptual framework. Mind Mapping tools can either be online or offline.

Top 10+ Free Mind Mapping tools

Here we list the best of free mind mapping tools. All of these are really great and worth trying.

1. FreeMind - FreeMind is a premier open source, free mind-mapping software written in Java. The recent development has turned it into high productivity tool. Operation and navigation of FreeMind is faster than that of MindManager because of one-click ”fold / unfold” and ”follow link” operations. FreeMind is available for Linux, Mac and Windows. Here is a review of FreeMind.
2. FreePlane - Freeplane is a great free and open source software to support thinking, sharing information and getting things done at work, in school and at home. It helps you with your mind map process.
3. Edraw Mind Map - Edraw Mind Map is a vector-based freeware with rich examples and templates. Easy to create basic flow charts, mind map, brainstorming diagram and sketch map. Edraw Mind Map is available for Windows.
4. Blumind - Blumind is a lightweight and powerful mind mapping tool, and it is free.
5. XMind - XMind, is an open source brainstorming and mind mapping software tool developed by XMind Ltd. It helps people to capture ideas, organize to various charts, and share them for collaboration. Supporting mind maps, fishbone diagrams, tree diagrams, org-charts, logic charts, and even spreadsheets. Often used for knowledge management, meeting minutes, task management, and GTD. XMind is compatible with FreeMind. The latest version is XMind 3. Xmind is available for Linux, Mac and Windows.
6. Bubbl.us - Create colorful mind maps online, Share and work with friends, Embed your mind map in your blog or website, Email and print your mind map
   Save your mind map as an image. Available on all OS/Platforms via browser.
7. Bookvar – Bookvar is an extremely easy and funny to use mind mapping tool. Creating mind maps with Bookvar is as easy and funny as playing computer games. You can build your mind maps in a matter of seconds by using handy keyboard shortcuts. You can drag files from your computer and drop them in the mind map. Stunning User Experience, Richer user interface built on top of Windows Presentation Foundation - Microsoft’s next generation UI framework. Slick, user-friendly interface based on the Office Fluent Ribbon. Cool 3D animation effects. Create mind maps together with your friends and colleagues. All you need is connection between computers. Each user receives a unique color which identifies topics created by him. Share thoughts and ideas using the integrated chat support. Add images directly in your topics. Embed and play movies. Attach other resources to your topics as files. Bookvar is available for Windows only.
8. Ekpenso - Create and share mind maps online, Make mind maps public or share them with groups or make them public, Export maps to XML, PDF, image or Freemind-files, Use ekpenso offline; Edit mind maps offline via Gears or Adobe AIR. Available on all OS/Platforms via browser.
9. Mind42 - Keep track of all your ideas, whether alone, with colleagues and friends or working together with the whole world. Mind42.com is a browser based online mind mapping application. With Mind42.com installing mind mapping tools is no longer needed - for a hassle-free mind mapping experience. Just open the browser and launch the application when needed. Available on all OS/Platforms via browser.
10. WiseMapping – Create powerful mind maps using the browser as you would with your desktop application. No installation is needed. publish, Share your mind maps and work with friends easily. Available on all OS/Platforms via browser.
11. Docear - Docear is free and open source, based on Freeplane
12. Calligra - Braindump is a tool to dump and organize the content of your brain (ideas, drawings, images, texts…) to your computer.
13. DabbleBoard - Dabbleboard is an online collaboration application that’s centered around the whiteboard. With a new type of drawing interface that’s actually easy and fun to use, Dabbleboard gets out of your way and just lets you draw. Draw with flexible & smart tools. Reuse previously-made drawings. All as naturally as using a marker or a pencil. And now with chat and document sharing, web conferencing with Dabbleboard is easier than ever. Amazingly smooth freehand mind map tool which is worth trying. Available on all OS/Platforms via browser.
14. MindRaider - MindRaider is personal notebook and outliner. It can also be used to create mind maps. It aims to connect the tradition of outline editors with emerging technologies. MindRaider mission is to help you in organization of your knowledge and associated web, local and realworld resources in a way that enables quick navigation, concise representation and infer referencing. Available on Windows, Linux and Java.
15. ThinkGraph - ThinkGraph is a 2D Drawing application specialized for Mind Maps and Concept Maps authoring. ThinkGraph lets the diagram to have relations link, Hypertext Links etc. ThinkGraph is available for MS Windows (not available for Linux, Mac).
16. GnuConcept - GnuConcept is a colaborative mind map tool for complex document creation. GnuConcept lets you draw the document concept map, edit all the concepts content and export it to several formats, like openoffice, xml or html.
    The GnuConcept Interfaz is divided in two frames: the drawarea frame, where you can draw the concept tree; and the textarea where you can write and edit the concept content. Available on Linux.

Other lesser known free Mind Mapping tools

There are lot many other free mind mapping tools available on the internet. here is a partial list;

1. Semantik - Semantik (previously Kdissert) is a mind mapping-like tool to help students to produce complicated documents very quickly and efficiently : presentations, dissertations, thesis, reports. While targetted mostly at students, Kdissert can also help teachers, decision maker, engineers and businessmen. Semantik is available exclusively for Linux and other free operating systems.
2. VUE - The Visual Understanding Environment (VUE) is an Open Source project based at Tufts University. The VUE project is focused on creating flexible tools for managing and integrating digital resources in support of teaching, learning and research. VUE provides a flexible visual environment for structuring, presenting, and sharing digital information. VUE is available on Linux, Mac and Windows.
3. DrawAnywhere - Draw Flowcharts, Process diagrams, Organizational charts online and more. Login from anywhere and modify your diagram. Share your diagram with others or link to your webpage. Export your diagram as an image file (jpg, png etc). No software to download. You just need a web browser with Flash player.
4. VYM – VYM (View Your Mind) is a tool to generate and manipulate maps which show your thoughts. Such maps can help you to improve your creativity and effectivity. You can use them for time management, to organize tasks, to get an overview over complex contexts. Available on FreeBSD, Linux, OS X.
5. ThoughtEx.Net - Simple software to capture ideas for Windows Vista and XP
6. Mapul - Mapul is a single web based project allows you to create completely organic looking mind maps. It is based on Microsoft silverlight technology on web.
7. Text2Mindmap - Text 2 Mind Map is a web application that creates a mind map out of a list of words.
8. MindNode – MindNode lets you create easy mind map and is exclusively for Mac user. It was created with the user in mind and features a very simple and intuitive user interface that lets the user focus on expressing and developing ideas. Nearly no time is required to learn the interface.
9. HyperGraph - HyperGraph is an open source project which provides java code to work with hyperbolic geometry and especially with hyperbolic trees. It provides a very extensible api to visualize hyperbolic geometry, to handle graphs and to layout hyperbolic trees.
10. Chartr – Chartr is another open source mind mapping tool for Linux clones with numerous features like mind maps with curved links, outline, box and color support.
11. Morcego - Morcego is a 3D network browser written in Java and released under LGPL license. Helps to create 3d Mind maps. Morcego is developed by University of Sao Paulo, Brazil.

There are more than 300 (including commercial Mind Map tools) and all are listed in http://www.mind-mapping.org. It is a comprehensive master list of mind mapping tools and a great reference site.