Notation

The term notation can refer to:

Written communication

• Phonographic writing systems, by definition, use symbols to represent components of auditory language, i.e. speech, which in turn refers to things or ideas. The two main kinds of phonographic notational system are the alphabet and syllabary. Some written languages are more consistent in their correlation of written symbol or grapheme and sound or phoneme, and are therefore considered to have better Phonemic orthography.
• Ideographic writing, by definition, refers to things or ideas independently of their pronunciation in any language. All of the notational systems listed below are ideographic. Some ideographic systems are also Pictograms that convey meaning through their pictorial resemblance to a physical object.

Biology and Medicine

• Nucleic acid notation
• Systems Biology Graphical Notation (SBGN) — orthogonal notations for Process Descriptions, Entity Relationships, and Activity Flows
• Pattern description notations used to describe sequence motifs
• Cytogenetic notation

Chemistry

• Chemical formulas are a way of expressing information about the atoms that constitute a particular chemical compound, e.g. H₂O or C₆H₁₂O₆
• Structural formulas are graphical representations of the molecular structure, showing how the atoms are arranged
• Nuclear notation provides a convention in chemistry and physics to indicate the atomic number and mass number of an isotope.

Computing

• BNF (Backus Normal Form or Backus–Naur Form) and EBNF (Extended Backus-Naur Form) are the two main notation techniques for context-free grammars.
• Hungarian notation is an identifier naming convention in computer programming, in which the name of a variable or function indicates its type or intended use.
• Mathematical markup languages are computer notations for representing mathematical formulae.

Dance and movement

• Benesh Movement Notation permits a graphical representation of human bodily movements
• Laban Movement Analysis or Labanotation permits a graphical representation of human bodily movements
• Eshkol-Wachman Movement Notation permits a graphical representation of bodily movements of other species in addition to humans, and indeed any kind of movement (e.g. aircraft aerobatics)
• Aresti aerobatic symbols provides a way to represent flight maneuvers in aerobatics

Logic

A variety of symbols are used to express logical ideas; see the List of logic symbols

Mathematics

• Mathematical notation is used to represent various kinds of mathematical ideas.
  • All types of notation in probability
  • Cartesian coordinate system, for representing position and other spatial concepts in analytic geometry
  • Notation for differentiation, common representations of the derivative in calculus
  • Big O notation, used for example in analysis to represent less significant elements of an expression, to indicate that they will be neglected
  • Z notation, a formal notation for specifying objects using Zermelo-Fraenkel set theory and first-order predicate logic
  • Ordinal notation
  • Set-builder notation, a formal notation for defining sets in set theory
• Systems to represent very large numbers
  • Conway chained arrow notation
  • Knuth's up-arrow notation
  • Steinhaus–Moser notation
• Numeral systems, notation for writing numbers, including
  • Arabic numerals
  • Roman numerals
  • Scientific notation for expressing large and small numbers
  • Sign-value notation, using signs or symbols to represent numbers
  • Positional notation also known as place-value notation, in which each position is related to the next by a multiplier which is called the base of that numeral system
    • Binary notation, a positional notation in base two
    • Octal notation, a positional notation in base eight, used in some computers
    • Decimal notation, a positional notation in base ten
    • Hexadecimal notation, a positional notation in base sixteen, commonly used in computers
    • Sexagesimal notation, an ancient numeral system in base sixty
• See also Table of mathematical symbols - for general tokens and their definitions...

Music

• Musical notation permits a composer to express musical ideas in a musical composition, which can be read and interpreted during performance by a trained musician; there are many different ways to do this (hundreds have been proposed), although staff notation provides by far the most widely used Modern musical symbols.

Physics

• Bra-ket notation or Dirac Notation is another representation of probability in quantum mechanics
• Tensor notation is a general way to represent a gravitational field in general relativity
• Feynman Diagrams permit a graphical representation of a perturbative contribution to the transition amplitude or correlation function of a quantum mechanical or statistical field theory

Typographical conventions

• Infix notation, the common arithmetic and logical formula notation, such as a+b-c
• Polish notation or "prefix notation", which places the operator before the operands (arguments), such as + a b
• Reverse Polish notation or "postfix notation", which places the operator after the operands, such as a b +

Other systems

• Baseball scorekeeping, to represent a game of baseball
• Chess notation, to represent moves in a game of chess
• New Epoch Art Notation, to represent the creation of a visual image using any physical media
• Hungarian notation, to represent the type or intended use of a variable within its name in computer programming
• Whyte notation

Various notations have been developed to specify regular expressions.