Digital electronic computer

In computer science, a digital electronic computer is a computer machine which is both an electronic computer and a digital computer. Examples of a digital electronic computers include the IBM PC, the Apple Macintosh as well as modern smartphones. When computers that were both digital and electronic appeared, they displaced almost all other kinds of computers, but computation has historically been performed in various non-digital and non-electronic ways: analog computers are examples of non-digital computers, and mechanical computers are examples of non-electronic computers. An example of a non-digital and non-electronic computer is the ancient Antikythera mechanism. All kinds of computers, whether they are digital or analog, and electronic or non-electronic, can be Turing complete if they have sufficient memory. A digital electronic computer is not necessarily a programmable computer, a stored program computer, or a general purpose computer.

A digital computer can peform its operations in the decimal system, in binary, in ternary or in other numeral systems. As of 2014, all digital electronic computers commonly used, whether personal computers or supercomputers, are working in the binary number system and also use binary logic. A few ternary computers using ternary logic were built mainly in the Soviet Union as research projects (googling for it can lead to some web-based simulators of those ternary computers).

People living in the beginning of the 21st century use digital electronic computers for storing data, such as photos, music, documents, and 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