In C#, what is the difference between public, private, protected, and having no access modifier?

Question

All my college years I have been using public, and would like to know the difference between public, private, and protected

Answer 1

A status of Private indicates that variables can only be accessed by objects of the same class. Protected status extends that access to include descendants of the class as well.

"from the above table we can see the deference between private and protected... am think both are same ....so what the need for that two separate command"

Check MSDN link for more information