Context-Free-Language (CFL)

A language L is said to be a Context-Free-Language (CFL) if its grammar is Context-Free. More precisely, it is a language whose words, sentences and phrases are made of symbols and words from a Context-Free-Grammar. Usually, CFL is of the form L=L(G). Given below are examples for CFG but not for CFL.
Here I am giving you one example of context-free grammar
Example:
A context-free grammar for the language consisting of all strings over {a,b} which contain a different number of a's to b's is
S → U | V
U → TaU | TaT
V → TbV | TbT
T → aTbT | bTaT | ε
Here, T can generate all strings with the same number of a's as b's, U generates all strings with more a's than b's and V generates all strings with fewer a's than b's.