Swift is Apple’s new programming language being used by developers inside and outside Apple to create new apps for macOS, iOS, watchOS, and tvOS. Most Apple operating systems and frameworks were written originally in Objective-C, and there are bridges between the two so that you can write new apps in Swift that use the Objective-C frameworks, sometimes without even knowing it. Examples and demos from Apple on http://developer.apple.com and at the Apple Worldwide Developer Conferences (WWDC) and Tech Talks now use Swift.
In and of itself, a new programming language isn’t an earth-shaking ...
