What is main use of Enumeration?

Question

What is main use of Enumeration in c#?

Edited:- suppose I want to compare the string variable with the any enumeration item then how i can do this

Answer 1

An enumeration type (also named an enumeration or an enum) provides an efficient way to define a set of named integral constants that may be assigned to a variable.

http://msdn.microsoft.com/en-us/library/cc138362.aspx