You might know that computers today use electrons to pass signals back and forth on silicon chips. But scientists are always looking for better and faster ways to send and store information, and are dreaming about what computers of the future would look like. One idea is that computers can be made smaller — much, much, smaller — only the size of a handful of atoms! This idea of very, very small computers is called quantum computing. Quantum computing is still a long way away, but scientists are hopeful that it could completely change the way we use computers. One group of scientists thinks we could make optical quantum computers: computers that use light to communicate. Light is made up of tiny particles called photons, and these photons could take the place of electrons to send signals back and forth inside the computer. What do you think a computer made out of light would look like?