When you push it, it is on. It springs back to off when you release it, which is different from a toggle switch, but it still is a binary device. There are many advantages to binary. Here are four somewhat overlapping important reasons for using binary:. These characteristics of binary were realized by Claude Shannon, a mathematician at Bell Telephone Laboratories.
To add another digit to the coding system would mean adding the ability to determine the strength i. The hardware to do ternary calculations - calculations involved three possible values - already exists. The first computer capable of performing such calculations was created in , and the first modern, electric version - the ternary computer - was built by the Soviet Union in While a ternary computer is potentially cheaper to manufacture and potentially more efficient in some ways, it seems that the rate of mass-production of binary computers has stalled further development.
Having said that, it is likely the way transistors are arranged and how they perform calculations that is the real reason we have stuck with binary for this long. Binary math is much easier for a computer to understand than ternary math. If you stack transistor switches together, you create a logic gate.
The gate compares two different input types i. This is how computers make decisions and is the basic principle of computer programming, with a program being made up of logical sets of instructions. These operations are based on a branch of mathematics called Boolean algebra. Boolean Logic states that there are four possible outcomes if you have two possible inputs as in a binary system.
Each of the logic gate operations can be expressed in a truth table:. Computers use binary numbers because this is the easiest and simplest way to record and process the electrical currents that run through their hardware. If there is an electrical current, the transistor switch is on.
The transistor switch is off if there is no electrical current. An on switch is represented by a 1 and an off switch by a 0. Each switch represents one single bit of information, and eight bits are known as a byte. This is how information is stored in computer memory. Ternary systems do exist but are not in common use. Author: Trey Williams. Why Do Computers use Binary Numbers? Binary vs. Modern computers work with discrete values — digits — rather than using electrical values as analogs to physical quantities.
That's why they're called digital computers. To design a decimal digital computer, we need ten electrical values to represent the digits zero to nine. Hypothetically, we might decide to use a signal of zero volts to represent the digit zero, one volt to represent the digit one, and so on up to nine volts to represent the digit nine.
That sounds OK, but manufacturing tolerances make it very difficult in practice. Taking tolerances into account, we'd design circuits so that, if the digit seven is represented by seven volts, 6.
We're trapped; our design cannot work in practice when manufactured in quantity. It is extraordinarily difficult to design and build electronic devices that reliably discriminate among ten discrete values.
Although it is hard to discriminate among ten discrete states with electronics, it is easy to discriminate between two. One type of digital logic circuit uses a voltage of zero to represent the digit zero and five volts to represent the digit one. Essentially, we are discriminating between off and on.
Anything less than about 2. It is relatively easy to build circuits that reliably discriminate between two values. The first of our two facts is this: Binary electronic circuits are reliable. The engineers of the s knew the difficulty of representing ten discrete values and the reliability of binary circuits, and so they designed ENIAC using binary electronic circuits.
Each decimal digit required ten binary devices arranged so that one was on and the other nine were off. The circuit that was on indicated the digit represented. A ten-digit number required more than vacuum tubes, a hundred to represent the digits and some more to control operations and to connect the circuits together. During that process, von Neumann observed that the ten devices needed for one decimal digit, if used as a ten bit binary number, could represent values from zero to 1, instead of only zero to nine.
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