metasyntax notation for context-free grammars, developed by John Backus and Peter Naur for the ALGOL 60 report (1963); foundational to formal language specification in computer science
In computer science, Backus–Naur form or Pāṇini–Backus Form (BNF or PBF, pronounced /ˌbækəs ˈnaʊər/), also known as Backus normal form, is a notation system for defining the syntax of programming languages and other formal languages, developed by John Backus and Peter Naur. It is a metasyntax for context-free grammars, providing a precise way to outline the rules of a language's structure.
It has been widely used in official specifications, manuals, and textbooks on programming language theory, as well as to describe document formats, instruction sets, and communication protocols. Over time, variations such as extended Backus–Naur form (EBNF) and augmented Backus–Naur form (ABNF) have emerged, building on the original framework with added features.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).