Pumping lemma is a negativity test which is used to determine whether a given language is non-regular

If a language passes the pumping lemma, it doesn‟t mean that the language is regular; it simply means that it is non-regular

There are two kinds of pumping lemma one for regular languages and one for context free languages.

Pumping lemma for regular languages states that If L is regular, then by P.L. for all x ∈L with |x| ≥ n such that ∃u, v, w such that

(1)x= uvw

(2) |uv| ≤ n

(3) |v| ≥ 1

(4)$ ∀ i ∈ N :uv^iw∈ L.$