about the coordinator design pattern in larman?

I was reading the 1st edition of UML and patterns from larman and in chapter 22.11 it talks about the coordinator pattern. i just understand that is an object that is between the view and the controller but i didnt understand why it is needed and when to use it. can someone explain to me how does this pattern works? maybe a simple code example.also is it the same than delegator?

thanks.