May any body explain what does "swiss army knife" mean in the following sentence:
"A mind Map is the swiss army knife of the brain."
The Swiss Army Knife has many different tools in it, so it can be used for an incredible number of actions. The sentence is suggesting that a Mind Map is used by the brain to solve many different problems.
Here's a picture of the knife to indicate its uses: Wenger | The Genuine Swiss Army Knife