Last year, Apple introduced Swift, a new programming language aimed at iOS and OSX app development, and it reached its second version at the company's WWDC developer event in June. Today, Apple has begun the process of fully open-sourcing the language.
As noted by Ars Technica, the company has launched its Swift developer comunity site, Swift.org, and put the Swift project up on GitHub.
Swift is also in the process of heading to version 3.0, and if you're interested in finding out more about that, you can read the "evolution" document for the language on GitHub.