number of different symbols is very large. Some examples of coding systems with the required number of symbols are:
– Binary code (q = 2 symbols, all electronic DP codes)
– Ternary code (q = 3, not used)
– Quaternary code (q = 4, e.g., the genetic code consisting of four letters: A, C, G, T)
– Quinary code (q = 5)
– Octal code (q = 8 octal digits: 0, 1, 2, …, 7)
– Decimal code (q = 10 decimal digits: 0, 1, 2, …, 9)
– Hexadecimal code [10] (q = 16 HD digits: 0, 1, 2, …, E, F)
– Hebrew alphabet (q = 22 letters)
– Greek alphabet (q = 24 letters)
– Latin alphabet (q = 26 letters: A, B, C, …, X, Y, Z)
– Braille (q = 26 letters)
– International flag code (q = 26 different flags)
– Russian alphabet (q = 32 Cyrillic letters)
– Japanese Katakana writing (q = 50 symbols representing different syllables)
– Chinese writing (q > 50,000 symbols)
– Hieroglyphics (in the time of Ptolemy: q = 5,000 to 7,000; Middle Kingdom, 12th Dynasty: q = approximately 800)
Criteria for selecting a code: Coding systems are not created arbitrarily, but they are optimized according to criteria depending on their use, as is shown in the following examples:
Pictorial appeal (e.g., hieroglyphics and pictograms)
Small number of symbols (e.g., Braille, cuneiform script, binary code, and genetic code)
Speed of writing (e.g., shorthand)
Ease of writing (e.g., cuneiform)
Ease of sensing (e.g., Braille)
Ease of transmission (e.g., Morse code)
Technological legibility (e.g., universal product codes and postal bar codes)
Ease of detecting errors (e.g., special error detecting codes)
Ease of correcting errors (e.g., Hamming code and genetic code)
Ease of visualizing tones (musical notes)
Representation of the sounds of natural languages (alphabets)
Redundance for counteracting interference errors (various computer codes and natural languages; written German has, for example, a redundancy of 66 %)
Maximization of storage density (genetic code)
The choice of code depends on the mode of communication. If a certain mode of transmission has been adopted for technological reasons depending on some physical or chemical phenomenon or other, then the code must comply with the relevant requirements. In addition, the ideas of the sender and the recipient must be in tune with one another to guarantee certainty of transmission and reception (see Figures 14 and 15). The most complex setups of this kind are again found in living systems. Various existing types of special message systems are reviewed below:
Acoustic transmission (conveyed by means of sounds):
– Natural spoken languages used by humans
– Mating and warning calls of animals (e.g., songs of birds and whales)
– Mechanical transducers (e.g., loudspeakers, sirens, and fog horns)
– Musical instruments (e.g., piano and violin)
Optical transmission (carried by light waves):
– Written languages
– Technical drawings (e.g., for constructing machines and buildings, and electrical circuit diagrams)
– Technical flashing signals (e.g., identifying flashes of lighthouses)
– Flashing signals produced by living organisms (e.g., fireflies and luminous fishes)
– Flag signals
– Punched cards, mark sensing
– Universal product code, postal bar codes
– hand movements, as used by deaf-mute persons, for example
– body language (e.g., mating dances and aggressive stances of animals)
– facial expressions and body movements (e.g., mime, gesticulation, and deaf-mute signs)
– dancing motions (bee gyrations)
Tactile transmission (Latin tactilis = sense of touch) (signals: physical contact):
– Braille writing
– Musical rolls, barrel of barrel-organ
Magnetic transmission (carrier: magnetic field):
– magnetic tape
– magnetic disk
– magnetic card
Electrical transmission (carrier: electrical current or electromagnetic waves):
– telephone
– radio and TV
Chemical transmission (carrier: chemical compounds):
– genetic code (DNA,
– Binary code (q = 2 symbols, all electronic DP codes)
– Ternary code (q = 3, not used)
– Quaternary code (q = 4, e.g., the genetic code consisting of four letters: A, C, G, T)
– Quinary code (q = 5)
– Octal code (q = 8 octal digits: 0, 1, 2, …, 7)
– Decimal code (q = 10 decimal digits: 0, 1, 2, …, 9)
– Hexadecimal code [10] (q = 16 HD digits: 0, 1, 2, …, E, F)
– Hebrew alphabet (q = 22 letters)
– Greek alphabet (q = 24 letters)
– Latin alphabet (q = 26 letters: A, B, C, …, X, Y, Z)
– Braille (q = 26 letters)
– International flag code (q = 26 different flags)
– Russian alphabet (q = 32 Cyrillic letters)
– Japanese Katakana writing (q = 50 symbols representing different syllables)
– Chinese writing (q > 50,000 symbols)
– Hieroglyphics (in the time of Ptolemy: q = 5,000 to 7,000; Middle Kingdom, 12th Dynasty: q = approximately 800)
Criteria for selecting a code: Coding systems are not created arbitrarily, but they are optimized according to criteria depending on their use, as is shown in the following examples:
Pictorial appeal (e.g., hieroglyphics and pictograms)
Small number of symbols (e.g., Braille, cuneiform script, binary code, and genetic code)
Speed of writing (e.g., shorthand)
Ease of writing (e.g., cuneiform)
Ease of sensing (e.g., Braille)
Ease of transmission (e.g., Morse code)
Technological legibility (e.g., universal product codes and postal bar codes)
Ease of detecting errors (e.g., special error detecting codes)
Ease of correcting errors (e.g., Hamming code and genetic code)
Ease of visualizing tones (musical notes)
Representation of the sounds of natural languages (alphabets)
Redundance for counteracting interference errors (various computer codes and natural languages; written German has, for example, a redundancy of 66 %)
Maximization of storage density (genetic code)
The choice of code depends on the mode of communication. If a certain mode of transmission has been adopted for technological reasons depending on some physical or chemical phenomenon or other, then the code must comply with the relevant requirements. In addition, the ideas of the sender and the recipient must be in tune with one another to guarantee certainty of transmission and reception (see Figures 14 and 15). The most complex setups of this kind are again found in living systems. Various existing types of special message systems are reviewed below:
Acoustic transmission (conveyed by means of sounds):
– Natural spoken languages used by humans
– Mating and warning calls of animals (e.g., songs of birds and whales)
– Mechanical transducers (e.g., loudspeakers, sirens, and fog horns)
– Musical instruments (e.g., piano and violin)
Optical transmission (carried by light waves):
– Written languages
– Technical drawings (e.g., for constructing machines and buildings, and electrical circuit diagrams)
– Technical flashing signals (e.g., identifying flashes of lighthouses)
– Flashing signals produced by living organisms (e.g., fireflies and luminous fishes)
– Flag signals
– Punched cards, mark sensing
– Universal product code, postal bar codes
– hand movements, as used by deaf-mute persons, for example
– body language (e.g., mating dances and aggressive stances of animals)
– facial expressions and body movements (e.g., mime, gesticulation, and deaf-mute signs)
– dancing motions (bee gyrations)
Tactile transmission (Latin tactilis = sense of touch) (signals: physical contact):
– Braille writing
– Musical rolls, barrel of barrel-organ
Magnetic transmission (carrier: magnetic field):
– magnetic tape
– magnetic disk
– magnetic card
Electrical transmission (carrier: electrical current or electromagnetic waves):
– telephone
– radio and TV
Chemical transmission (carrier: chemical compounds):
– genetic code (DNA,
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