What is Objective-C language?

Objective-C language is an object-oriented programming language developed by TomLove and BradCox in 1983. It was originally developed for the NextSTEP operating system, and was later acquired by Apple, which became the basis of iOS and macOS operating systems. Therefore, Objective-C language has become one of the most important programming languages in the development of iOS and macOS applications.

Target -C language is based on C language and is a strict superset. It adds many object-oriented features, such as encapsulation, inheritance and polymorphism. Objective-C language uses message passing mechanism to communicate between objects. In Objective-C language, all function calls are regarded as message passing between objects.

The memory management of Objective-C language is realized by reference counting. Each object has a counter. When an object is referenced, the counter automatically increments 1. When the object is no longer referenced, the counter is automatically decremented by 1. When the counter is 0, the object is released.

Different from other programming languages, Objective-C language adopts dynamic binding mechanism. The type of an object is uncertain at compile time and can only be determined at run time. This mechanism makes Objective-C language more flexible and extensible, which is one of the reasons why it is widely used.

In recent years, Apple has introduced the Swift language, claiming to be the successor of Objective-C. Compared with Objective-C, Swift language is simpler and clearer, and its grammar is easier to learn and understand. However, Objective-C language still plays an important role in Apple's products.

Generally speaking, Objective-C language is an important object-oriented programming language, which is widely used in the development of iOS and macOS applications. For programmers who want to enter the field of iOS/macOS development, learning Objective-C language is the only way.