![cover image](https://wikiwandv2-19431.kxcdn.com/_next/image?url=https://upload.wikimedia.org/wikipedia/commons/thumb/d/da/Formal_languages.svg/640px-Formal_languages.svg.png&w=640&q=50)
Symbol (formal)
Token in a mathematical or logical formula / From Wikipedia, the free encyclopedia
This article is about symbols in formal language theory. For other uses, see Symbol (disambiguation).
A logical symbol is a fundamental concept in logic, tokens of which may be marks or a configuration of marks which form a particular pattern.[citation needed] Although the term "symbol" in common use refers at some times to the idea being symbolized, and at other times to the marks on a piece of paper or chalkboard which are being used to express that idea; in the formal languages studied in mathematics and logic, the term "symbol" refers to the idea, and the marks are considered to be a token instance of the symbol.[dubious – discuss] In logic, symbols build literal utility to illustrate ideas.
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/thumb/d/da/Formal_languages.svg/300px-Formal_languages.svg.png)