.net - What do two left-angle brackets "<<" mean in C#?

Question

Basically the questions in the title. I'm looking at the MVC 2 source code:

[Flags]
public enum HttpVerbs {
    Get = 1 << 0,
    Post = 1 << 1,
    Put = 1 << 2,
    Delete = 1 << 3,
    Head = 1 << 4
}

and I'm just curious as to what the double left angle brackers << does.

Answer 1

When you write

1 << n

You shift the bit combination 000000001 for n times left and thus put n into the exponent of 2:

2^n

So

1 << 10

Really is

1024

For a list of say 5 items your for will cycle 32 times.