5
Context Free Grammar
5.1 CONTEXT FREE GRAMMAR: DEFINITION AND EXAMPLES
Q. Define context free grammar. Why is it called context free?
Ans. According to Chomsky Hierarchy, Context Free Grammar (CFG) is Type 2 Grammar.
In mathematical description we can describe it as
Where all the production are in the form α → β, where α 
VN, i.e. set of non-terminals and /α/ = 1, i.e. there will be only one non-terminal at the left-hand-side and β VN U Σ, i.e. β is a combination of non-terminals and terminals.
Before describing why this type of grammar is called ...
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