Cocoa (Software framework) Mac OS 13 Object-oriented programming (Computer science) 10 Computer Science 7 Engineering & Applied Sciences 7 Application program interfaces (Computer software) 6 C (Computer program language) 4 Objective-C (Computer program language) 3 Operating systems (Computers) 3 iOS (Electronic resource) 3 Application software 2 Development 2 Macintosh (Computer) 2 Programming 2 Swift (Computer program language) 2 Cocoa (Application development environment) 1 Computer security 1 Mobile computing 1 Xcode 1 iPhone (Smartphone) 1