Why is there String/string and Object/object in C#?

Question

Possible Duplicate:
String vs string in C#

I know there is no difference between using string and String. But, why is there the option in C#? Is it the same for object and Object?

EDIT

Note, that I am asking why.

Answer 1

http://stackoverflow.com/questions/215255/string-vs-string-in-c

Answer 2

In the MS implementation of the C# standards, string maps to System.String and object maps to System.Object. In other implementations, this could map to other classes. So if you use string and object, you are on the safer side if you should ever compile it with another compiler.

Answer 3

string is just an alias for System.String. It is jsut a shorthand the same way that int is shorthand for System.Int32