Objective-C is an object-oriented programming language that is a kind of extension to the C programming language. Although Objective-C is a general-purpose language, it has mainly been used to make applications for the Apple OS X and iOS operating systems. It is possible that Objective-C will be less important in the future as Apple has introduced a new programming language called Swift.
The following links will provide information about Objective-C.
The table below contains links to some examples of Objective-C programs. As Objective-C is an extension of the C programming language, the programs provided in the C language page are also valid Objective-C programs.