βThe concept of sets is basic to all mathematics and mathematical applications. This concept is very simple. We come across sets of different kinds in our daily life. For example, a class is a set of students. The Indian cricket team is a set of players. Thus, by a set we mean a collection of objects. However, in Mathematics, we define a set to be a well defined collection of objects. The meaning for well defined is given as looking at a set and an object it is possible to decide whether the object belongs to the collection or not.
Georg Cantor was a Russian-German mathematician who created modern set theory and extended it to give the concept of transfinite numbers, with cardinal and ordinal number classes. Cantor visited Switzerland in 1872 there he met Richard Dedekind their friendship grew up which lasted for many years. Numerous letters between them in the years 1873-1879 are preserved. It is very clear that Dedekind's deep abstract logical way of thinking was a major influence on Cantor as his ideas developed.
1845 - 1918