The thinking brain is the cerebrum, which looks mostly the same all over—like a bowl of squishy, wrinkled gelatin. Actually, it looks like two bowls.
Humans have two brains, one on each side of the head. The right cerebrum and the left cerebrum are mirror images of each other, connected by a thin cord.
Two brains are better than one. If you had to stuff and seal a million envelopes, wouldn’t it be faster if you stuffed them while a friend sealed them? You would each focus on a single task while cooperating to complete the whole job. That’s roughly how the right and left brains work. The right brain controls the left side of your body, and the left brain controls the right side. Each brain may look like a mirror image of the other, but they are in charge of different activities. The illustration below shows which side of the brain handles tasks in most people—but not all—because not everyone is the same.