Derivation is used to find whether the string belongs to a given grammar.
Types
• Leftmost derivation.
• Rightmost derivation.
In leftmost derivation, at each and every step the leftmost non-terminal is expanded by substituting its corresponding production to derive a string.
Example
In rightmost derivation, at each and every step the rightmost non-terminal is expanded by substituting its corresponding production to derive a string.
Example