After the introduction of fuzzy sets' by Prof. Lotfi Zadeh in 1965, work on fuzzy sets has been increasing exponentially. People from diverse area of study have shown much interest in fuzzy sets due to its rich potential for applications. In the mean time various other generalizations of the classical set theory( like, multisets or bags, intuitionistic fuzzy sets, rough sets, soft sets, vague sets etc.) have also been found and alongwith their applications in different fields. The present works deals with the basic concepts of fuzzy sets, bag theory, rough sets, soft sets and fuzzy soft sets and intuitionistic fuzzy soft sets together a few applications