Why can I create a class named “var”?

Question

Isn\'t var a keyword in C#? But why can I do this:

public class var { }

public class main
{
    public static void main(string[] args)
    {
           


        

Answer 1

var is not a keyword according to this list.

it is a contextual keyword, so from the context the compiler is able to decide which is your class and which is the contextual keyword, and no confusion arises.

a contextual keyword is:

used to provide a specific meaning in the code, but it is not a reserved word in C#.

so as its not reserved you can use it.

As pointed out in the comments above there is a discussion of the differences as well as a list of the various keywords and contextual keywords added at each version of c# on Eric Lipperts blog

It is interesting to note that since the set of keywords were decided upon in C#1.0 there have been no additions, so as to preserve backwards compatibility.