XMind is strong contender to mind mapping applications like TheBrain available on Linux. Recording and organizing thoughts is highly recommended if you are in a continuously evolving profession. XMind seem to get it right. The free version has some limitations related to exporting the maps and supported artefacts but is professional enough to get novice or advanced mappers going.

Features (in Free version)

All kind of diagrams

Mind Toolbox (includes “Relationship”, “Boundary”, “Summary”, “Labels”, “Markers”, “Notes”, and “Drill Down”)

Local network sharing

Save to Evernote

Share on web

Available library of sample mind maps, open to contribution as well

Multi-platform: supports Linux, Windows and Mac

The free version is open source

Installation

You can download XMind from its website.

Webpage: XMind