UP to more information about BNF, Syntax Diagrams and EBNF Style Name and link Rule Items Concat (default space) Choice Optional Repetition Grouping Other Comment Terminal Non Terminal 0 or more 1 or more n n to m Other BNF BNF (Algol 60) <name>::=... ... <...> | note1 note2 note3 note5 Intermediate ANSI C name: ... bold italics indented line one of ... opt note2 note3 note5 BNF-like description of URLs name ... ... ... | [...] note2 note3 note5 Wirth Wirth name=... . "..." ... | [...] {...} note4 (...) SAIF and Bungisoft <name>::=... "..." <...> | [...] {...} note4 (...) note5 EBNF from Compiler Basics by J.A.Farrell name:==... '...' ... | or [...,...] [...] {...}* {...} note5 Pascal EBNF Definition name ... "..." bold <...> | [...] {...} note4 (...) note5 ISO Extended Pascal name=... . name>... . `...' ... | [...] {...} note4 (...) (*...*) ISO EBNF...