Cocoa
is a native compilation environment on Mac OS x systems. He contains two frames, which are actually a series of libraries, Foundation and AppKit.
On your iphone and other handheld devices, use one of his subcategories-Cocoa Touch. The Foundation framework he supports is the same as cocoa, but his user graphics library is Uikit, which is specially designed for handheld devices and provides an interface on your device.
Cocoa Touch and Cocoa a distinct difference is that Cocoa touch does not support the garbage collection mechanism, which means that you have to manage your memory in your code.
Foundation
Provides a series of underlying data types, as well as enumeration, container support. The class name from this framework begins with NS.
UIKit
The user graphics package on iOS. The class at the beginning of the UI comes from this framework.
Different from the user graphics package on Mac OS X, the graphic class above is from AppKit and the class name begins with NS.
Objective-c
A language for application development on iOS and Mac OS X, and is also used by the foundation and Uikit frameworks to become Yu Yang.
It is a superset of C language, object oriented.
XCode
An IDE on Mac OS x that is used primarily for code writing.
Interface Builder
Part of Xcode that is used primarily for UI design.
Concepts of Cocoa, Foundation, UIKit, Objective-c, XCode, Interface Builder