ebnf:

        
    EBNF stands for Extended Backus-Naur Form, or Extended Backus Normal Form. It is an extension to BNF and is used to describe the syntax of context-free grammars, such as programming languages, document formats, or communication protocols. It improves over BNF by providing operators to express optional, zero or more, and one or more occurrences of a term. This makes EBNF much more expressive and concise compared to BNF.