Backus Normal Form

What Does Backus Normal Form Mean?

Backus Normal Form (BNF) is a metasyntactic notation procedure used to specify the syntax of computer programming languages, command/instruction sets, document formatting and communication protocols. BNF is applied when language descriptions are required.

Techopedia Explains Backus Normal Form

A BNF specification is a derivation rule set that is usually written as follows:

The <symbol>::_expression_where <symbol> is a non terminal
The _expression_consists of one or more symbol sequences.
A vertical bar (|) delineates other sequence options.
Symbols not appearing on the left side are terminals.
Symbols appearing on the left side are located within the symbol-expression pair and are non-terminals.

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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…

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