A mind map is basically a simple way to think-through problems, or "brainstorm" thoughts & ideas naturally without fretting over process and structure. It allows you to visually arrange your thoughts to aid with analysis and recall.
In a nutshell, a mind map is a diagram for representing tasks, words, projects, or items linked to a core concept or subject using a non-linear flow which allows the user to build an intuitive framework around a the concept. A mind map can help turn a long list of monotonous information into a colorful, memorable and highly organized diagram that works in conjunction with your brain's natural way of doing things.
For many users, a mind map can be used as a simplified content management system (CMS). It allows you to store all your data in a centralized location to stay organized. You can easily attach files to different branches for even more flexibility. You can also change to various different views in order to find one that suits you best.