Cocoa can be used with many programming languages. For a language to use Cocoa, that language must support a degree of flexibility and a model of object orientation that is compatible with Cocoa. Objective-C, Java, and many scripting languages integrate well with Cocoa. Other languages such as standard C and C++ can use Cocoa either by using only the C functions provided by the Objective-C runtime or by using Objective-C and Objective-C++ compilers to mix Objective-C code with the standard C and C++ code.
Now that the languages used to write Cocoa applications have been explained, the next step is to learn the tools used to create Cocoa applications. Chapter 3, "Using Apple's Developer Tools," introduces the tools that Apple provides for creating Cocoa applications. Apple's developer tools can be used with C, C++, Java, Objective-C, Objective-C++, and AppleScript.