In mathematics, computer science and linguistics, a formal language is one that has a particular set of symbols, and whose expressions are made according to a particular set of rules. The symbol is often used as a variable for formal languages in logic.
Unlike natural languages, the symbols and formulas in formal languages are syntactically and semantically related to one another in a precise way. As a result, formal languages are completely (or almost completely) void of ambiguity.
Some examples of formal languages include:
A formal language can be specified in a great variety of ways, such as:
- Strings produced by some formal grammar (see Chomsky hierarchy)
- Strings described or matched by a regular expression
- Strings accepted by some automaton, such as a Turing machine or finite state automaton
- Strings indicated by a decision procedure (a set of related yes/no questions) where the answer is 'yes'
- Language for languages in general
- Syntax for the form of a language in general
- Semantics for the meanings in a language
- Natural language for languages that are not formal
- Computer language for application of formal languages in computing
- Programming language for the application of formal languages to program computers
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- "1.11. Formal and Natural Languages — How to Think like a Computer Scientist: Interactive Edition". runestone.academy. Retrieved 2020-10-09.
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|edition=has extra text (help), chapter 6 Algebra of formalized languages.
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