It possesses many highly specialized component parts each associated with specific tasks, for example memory and vision. The functioning of the human brain not only allows us to sense our environment and coordinate movements but also gives rise to attributes such as consciousness. The latter is difficult to define but includes such attributes as a sense of past and future, an inner voice and self-awareness.
Intelligence appears to be the outward sign of a conscious being.
It is the result of millions of years of evolution - the distant origins of the human brain can be seen in simple reptiles and mammals. The most striking feature of the human brain is seen in the cortex. This is the folded, hemispherical structure which constitutes the bulk of the visible brain. It is not present in reptiles. The cortex is relatively recent.