Throughout this thesis, all rings are associative with identity. We studied nilpotent elements, reduced rings and a generalization of reversible rings based on articles by Junchao Wei, Libin Li, Zhao Liang and Yang Gang. A ring R is said to be reduced if R has no non-zero elements. It is easy to see that reduced ring R have the property ab=0 implies that ba=0 for all . Rings with later property was called reversible in [7] where the term zero commutative is used for such rings. Clearly reversible rings have the property ab=0 implies that aRb=0 for all , this property was called insertion of factors in [9],symmetricI (SI) in [26] and has been called semicommutative in [10]. Because elsewhere in the literature semicommutative means other things we use the term zero insertive (zi) of [8] for such rings. A ring R is called 2-primal if , where is the prime radical of R and is the set of all nilpotent elements in R. Shin in 1973 introduced the concept of 2-primal rings and several authors investigated this rings. We proved that reduced rings are 2-primal, N-regular left N-duo. Moreover in this thesis we investigated NI,NCI and min-left semicentral rings. A ring R is called min-left semicentral if every element of is left semicentral in R where the set of all left minimal idempotents elements of R. Clearly, these rings are proper generalization of abelian rings i.e. every idempotent element of R is central. NI rings are almost completely characterized by Marks in 2001. But surprisingly, some very natural characterizations of such rings seemed to have so far escaped notice. If R is NI ring, then R is min-left semicentral ring but NCI rings need not be left-semicentral. A ring R is called quasi-normal ring if for any where the set of all idempotent elements of R. We showed that quasi-normal rings are directly finite and min-left semicentral but the converse need not be true.