In COMPUTER science, Backus-Naur Form (BNF) is a metasyntax used to express context-free grammars: that is, a formal way to describe formal languages. JOHN Backus and Peter Naur developed a context free GRAMMAR to define the syntax of a programming language by using two sets of RULES: i.e., lexical rules and syntactic rules.

BNF is widely used as a notation for the grammars of computer programming languages, instruction sets and COMMUNICATION protocols, as well as a notation for representing parts of natural language grammars.

In computer science, Backus-Naur Form (BNF) is a metasyntax used to express context-free grammars: that is, a formal way to describe formal languages. John Backus and Peter Naur developed a context free grammar to define the syntax of a programming language by using two sets of rules: i.e., lexical rules and syntactic rules.

BNF is widely used as a notation for the grammars of computer programming languages, instruction sets and communication protocols, as well as a notation for representing parts of natural language grammars.