Augmented Backus–Naur form

Augmented Backus–Naur Form (ABNF) is a notation used to express the syntax of languages, particularly programming languages and data formats. It is an extension of the original Backus–Naur Form (BNF), which was developed by John Backus and Peter Naur in the 1960s. ABNF incorporates several enhancements and features that make it more expressive and convenient compared to standard BNF.