EBNF diagram symbol meanings

Question 1

abc “(“

Answer 1

Terminal symbol for a literal. The characters abc are written as they appear. Quotes are used to enclose symbols used by the metalanguage.

Question 2

< Item >

Answer 2

Non-terminal symbol. Item is defined elsewhere.

Question 3

< 1 > | < 2 >

Answer 3

“or” a choice between two alternatives. Either Item1 or Item2.

Question 4

a | b

Answer 4

“is defined as”. Item can take the value a or b

Question 5

[ ]

Answer 5

Optional part.

Question 6

{ }

Answer 6

Possible repetition.

Question 7

< 1 > { 1 }

Answer 7

Repetition.

Question 8

(FOO) | BOO

Answer 8

Grouping. A Foogle is an Item followed by the reserved word FOO or it is the reserved word BOO.