Binary code can provide a way to simplify the representation of information. In a binary code there are only two digits: one and zero. Typical binary codes will use strings of ones and zeros to represent letters, numbers, or other concepts. An example is binary representations of the American standard code for information interchange (ASCII), where each eight character string is able to represent any one of 256 different variations. Binary codes are often used in computing and other electronics, though they have also been present throughout human history in other forms.
In order for a binary code to represent text, computer processor instructions, or other information, it must be divided into discrete strings. These are often referred to at bit strings, and they may be either fixed or dynamic in length. In this context, bit refers to each binary digit, so an eight character string of binary code would contain eight bits of information. Using different character encodings or sets, bit strings like these can be made to represent many different things.
Computers and other electronics use what are known as flip flop circuits to represent information in binary code. These circuits can vary in design, though they typically must be able to exist in two discrete states. In computing, a flip flop circuit will usually represent a one with a positive voltage and a zero with no voltage. Early examples of this design involved the use of bulky vacuum tubes, and later breakthroughs leading to items such as transistors and microchips. Components like dynamic random access memory (DRAM) can use flip flop circuits to store binary codes.
Complex forms of data can also be stored in binary code, often in discrete strings of eight bits each. A binary file can be anything from a plain text document to an executable program, and the data contained within will be represented in the same ones and zeros as any binary code. Since a binary file can contain images, sounds, or virtually any other kind of information, they typically include a header that a computer can use for identification purposes.
Binary codes have been around much longer than modern computers, and examples of data being represented by two discrete states are found throughout much of human history. The ancient concept of feng shui uses several binary sets in the form of yao symbols, each of which represents yin or yang. A Nigerian tribe also used a binary set of either a circle or two lines to represent information for thousands of years. Another form of binary code unrelated to computing is Braille, which uses groups of six dots to represent letters or numbers. Each dot is capable of existing in one of two states, either raised or flat, so that they can be read by the blind.