Cocoa Touch is the name commonly used for Apple's vast collection of frameworks for iOS.

SwiftUI is a cross-platform toolkit that lets us build apps for iOS, macOS, tvOS, and watchOS.

While UIKit and AppKit have much in common, WatchKit is significantly different – and significantly simpler.

WatchKit was Apple’s native user interface toolkit for watchOS before SwiftUI was introduced.

Like UIKit it contains things like buttons, text boxes, and more, although focused on macOS rather than iOS.

AppKit is Apple’s native user interface toolkit for macOS.

It contains things like buttons, text boxes, navigation controls and more, and you drive it using Swift.

UIKit is Apple’s native user interface toolkit.

It contains the functionality for building programs, but doesn’t handle anything like user interfaces, audio or networking.

Swift is Apple’s modern programming language that lets you write apps for iOS, macOS, and other platforms.

tvOS is a spin off of iOS designed to run on televisions connected to Apple TV devices.

watchOS is the name for Apple’s tiniest operating system, and is responsible for running native apps and also delivering notifications from the phone.

macOS is the name for Apple’s desktop operating system, which is the technological grandparent of iOS, tvOS, and even watchOS.

It’s responsible for all the basic operations of the phone, such as making phone calls, drawing on the screen, and running apps.

iOS is the name of the operating system that runs on all iPhones and iPads.

While that's downloading, I can explain a couple of the absolute basics to you: So, your first action is to click here to install Xcode from the Mac App Store – it’s quite a big download, so start downloading it now and carry on reading. It’s free from the Mac App Store, and it's required to do development for Apple’s platforms.

Xcode is Apple’s programming application for developers. How to install Xcode and create a playground

Xcode download