macOS Learning to program with Xcode.

I don't have much programing experience, a little Fortran in college a few years ago and that' as far as it goes. But I do find learning this kind of things easy and I like it.

So I downloaded Xcode and the iPhone SDK, and I'm really interested in learning to use it. Problem is, I don't know were to start. What should I learn first? What programming language? Objective-C?

Thanks.

Thanks for the link. I think I had already seen that one.

What happens is that I don't know any programming language. I read the one used for Xcode is Objective-C. I'm reading something and trying to learn it, but I don't know how al comes together.

I mean, what are the steps to follow? What should I learn first? And afterwards, how does one comes up into creating an application? What is the difference between Cocoa, Objective-C and how it all comes together in Xcode?

I know they are a lot of question, but I am lost on were to start. I don't think I'm understanding why Xcode comes with soo many tools and options.