{mindmaps} are graphical representations of concepts or ideas, together with other related concepts and annotations. {tikz-pgf} provides a mindmap library for drawing {mindmaps}.
A mindmap is a graphical representation of a concept together with related concepts and annotations. Mindmaps are, essentially, trees, possibly with a few extra edges added, but they are usually drawn in a special way: The root concept is placed in the middle of the page and is drawn as a huge circle, ellipse, or cloud. The related concepts then "leave" this root concept via branch-like tendrils.

\begin{tikzpicture}
\path[mindmap,concept color=black,text=white]
node[concept] {Computer Science}
[clockwise from=0]
% note that `sibling angle' can only be defined in
% `level 1 concept/.append style={}'
child[concept color=green!50!black] {
node[concept] {practical}
[clockwise from=90]
child { node[concept] {algorithms} }
child { node[concept] {data structures} }
child { node[concept] {pro\-gramming languages} }
child { node[concept] {software engineer\-ing} }
}
child[concept color=blue] {
node[concept] {applied}
[clockwise from=-30]
child { node[concept] {databases} }
child { node[concept] {WWW} }
}
child[concept color=red] { node[concept] {technical} }
child[concept color=orange] { node[concept] {theoretical} };
\end{tikzpicture}
The above was description was taken from the tikz/pgf package documentation.