Quasi-filters of BE-algebras
Several types of algebraic structures have been studied so far in the literature of Mathematics. In abstract algebras, the main emphasis is given to the study of algebraic structures and their properties. Though there are many different views on algebraic structures, the central idea of an algebraic structure is a system involving one or more sets equipped with one or more n-ary operations satisfying a given set of axioms. Universal algebras is another branch of mathematics that studies algebraic structures in general. In light of universal algebras, many algebraic structures can be divided into varieties and quasi-varieties depending on the axioms used.