According to Product Design, a concept map, or mind map is a diagram used to represent ideas linked to, and arranged radially around, a central key word or idea.
Mind mapping involves writing down a central idea and thinking up new and related ideas, which radiate out from the center. By focusing on key ideas, and then looking for branches out and connections between the ideas, you can map out your knowledge in a manner that will help reframe your knowledge.
When you take the time to concept map your topic, you're breaking your research into smaller, more manageable parts.
In my example, the Tuskegee Airmen's history spans prewar to postwar American history. In order to better understand the impact of the Tuskegee Airmen, we will look at over-all desegregation of the American military (begun with executive order 9981), the prewar years and the training of African American pilots, as well as the post-war years and the Civil Rights movement.
Your concept map can also serve as a rough draft for your essay outline.