enable humanity to build even more powerful electronic computers. One such possible development is the memristor. People living in the beginning of the 21st century use digital electronic computers for storing data, such as photos, music, documents, for performing complex mathematical computations, or for communication, commonly over a worldwide computer network called the internet which connects many of the world's computers. All these activities made possible by digital electronic computers could, in essence, be performed with non-digital or non-electronic computers if they were sufficiently powerful, but it was only the combination of electronics technology with digital computation in binary that enabled humanity to reach the computation power necessary for today's computing. Advances in quantum computing, DNA computing, optical computing or other technologies could lead to the development of more powerful computers in the future. Digital computers are inherently best described by discrete mathematics, while analog computers are most commonly associated with continuous mathematics. The philosophy of digital physics views the universe as being digital. Konrad Zuse wrote a book known as Rechnender Raum in which he described the whole universe as one all-encompassing computer. See also Abacus ENIAC EDVAC List of vacuum tube computers History of computing hardware List of transistorized computers Computers