Since the brain was here long before computers, some might ask if computers can replicate some of the functions of the brain or in any way is like a brain. Although brains are not computers, the two entities (brain and computers) do have some similarities. For example, both need an energy source—and it must be a compatible energy source. A computer typically runs on electricity or solar power. There are several different types of voltages: 110, 120, 130, 220, 230, 240, and so on. A computer must have a transformer to us a voltage that is not compatible with the way in which the computer was built. The brain runs on an energy source, too. It uses electricity (generated by water much as a hydroelectric plant generates electricity), oxygen, chemical interactions, and glucose as energy sources—to name a few. More tomorrow.