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Binary code

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A binary code is a way of representing text or computer processor instructions by the use of the binary number system's two-binary digits 0 and 1. This is accomplished by assigning a bit string to each particular symbol or instruction. For example, a binary string of eight binary digits (bits) can represent any of 256 possible values and can therefore correspond to a variety of different symbols, letters or instructions.

In computing and telecommunication, binary codes are used for any of a variety of methods of encoding data, such as character strings, into bit strings. Those methods may be fixed-width or variable-width. In a fixed-width binary code, each letter, digit, or other character, is represented by a bit string of the same length; that bit string, interpreted as a binary number, is usually displayed in code tables in octal, decimal or hexadecimal notation. There are many character sets and many character encodings for them.

A bit string, interpreted as a binary number, can be translated into a decimal number. For example, the lowercase "a" as represented by the bit string 01100001, can also be represented as the decimal number 97.

History of Binary Code

Binary numbers were first described in Chandashutram written by Pingala in 100 BC. Binary Code was first introduced by the German mathematician and philosopher Gottfried Wilhelm Leibniz during the 17th century. Leibniz was trying to find a system that converts logic’s verbal statements into a pure mathematical one. After his ideas were ignored, he came across a classic Chinese text called ‘I Ching’ or ‘Book of Changes’, which used a type of binary code. The book had confirmed his theory that life could be simplified or reduced down to a series of straightforward propositions. He created a system consisting of rows of zeros and ones. During this time period, Leibiniz had not yet found a use for this system.[1]

Another mathematician and philosopher by the name of George Boole published a paper in 1847 called 'The Mathematical Analysis of Logic' that describes an algebraic system of logic, now known as Boolean algebra. Boole’s system was based on binary, a yes-no, on-off approach that consisted the three most basic operations: AND, OR, and NOT.[2] This system was not put into use until a graduate student from Massachusetts Institute of Technology by the name Claude Shannon noticed that the Boolean algebra he learned was similar to an electric circuit. Shannon wrote his thesis in 1937, which implemented his findings. Shannon's thesis became a starting point for the use of the binary code in practical applications such as computers, electric circuits, and more.[3]

Other forms of Binary Code

The bit string is not the only type of binary code. A binary system in general is any system that allows only two choices such as a switch in an electronic system or a simple true or false test.

Braille

Braille is a type of binary code that is widely used by blind people to read and write. This system consist of 6 dot positions, three in each column. Each dot has two states, raised or not raised.

Ba gua

The ba gua are diagrams used in feng shui, Taoist cosmology and I Ching studies. The ba gua consists of 8 trigrams; bā meaning 8 and guà meaning divination figure. The same word is used for the 64 guà (hexagrams). Each figure combines three lines (yáo) that are either broken (yin) or unbroken (yang). The relationships between the trigrams are represented in two arrangements, the primordial, "Earlier Heaven" or "Fuxi" bagua, and the manifested, "Later Heaven,"or "King Wen" bagua.[4] (See also, the King Wen sequence of the 64 hexagrams).

Ifá divination

Sixteen Principal Odú
Ogbe   I I I I   Ogunda   I I I II
Oyẹku   II II II II   Ọsa   II I I I
Iwori   II I I II   Ika   II I II II
Odi   I II II I   Oturupọn   II II I II
Irosun   I I II II   Otura   I II I I
Iwọnrin   II II I I   Irẹtẹ   I I II I
Ọbara   I II II II   Ọsẹ   I II I II
Ọkanran   II II II I   Ofun   II I II I

Ifá is the ancient system of divination and literary corpus of the Yoruba people of Nigeria. In Yoruba religion, the rite provides a means of communication with spiritual divinity. The Orisa Ifá or Orunmila ("Grand Priest") permits access to an initiated priest, a Babalawo ("father of the secrets") who generates binary values using sacred palm nuts. In wood powder, these are recorded as single and double lines. There are 16 principal Odú that are said to compose the 256 Odú. From memory alone, a Babalawo must be able to recite four to ten verses for each of the 256 Odú Ifá: generally, orisa lore, traditional medicine, and ritual advice. In 2005, UNESCO listed Ifá in the Masterpieces of the Oral and Intangible Heritage of Humanity.

Coding Systems

ASCII code

The American Standard Code Information Interchange, or ASCII, uses a 7 bit binary code to represent text within a computer, communications equipment, and other devices that use text. Each letter or symbol is assigned to a number from 0 to 127. For example, in the 8-bit ASCII code, a lowercase "a" is represented by the bit string 01100001.

Binary-coded Decimal

Binary-coded decimal, or BCD, is a binary encoded representation of integer values that uses a 4-bit nibble to encode decimal digits. Four binary bits can encode up to 16 distinct values; but, in BCD-encoded numbers, only the first ten values in each nibble are legal, and encode the decimal digits zero, through nine. The remaining six values are illegal, and may cause either a machine exception or unspecified behavior, depending on the computer implementation of BCD arithmetic.

BCD arithmetic is sometimes preferred to floating-point numeric formats in commercial and financial applications where the complex rounding behaviors of floating-point numbers is inappropriate.[5]

Early uses of Binary codes

Current uses of Binary

Besides computers, there are many things that use binary including:

  • CDs, which have a series of hills and valleys on the surface, which either reflect the light of the thin laser shone on them, representing a one, or do not, representing the zero.

Weight of binary codes

The weight of a binary code, as defined in [1], is the Hamming weight of the binary words coding for the represented words or sequences.

See also

Notes

  1. ^ Gottfried Wilhelm Leibniz (1646-1716)
  2. ^ What's so logical about boolean algebra?
  3. ^ Claude Shannon(1916-2001)
  4. ^ Wilhelm, Richard (1950). The I Ching or Book of Changes. Princeton, NJ: Princeton University Press. pp. 266, 269. ISBN 0-691-09750-X. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  5. ^ "General Decimal Arithmetic".
  6. ^ a b c Glaser 1971
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