Objective-C is the programming language to create iOS applications. iOS applications include, web based applications, native apps and hybrid apps. iOS is the operating System of iPhone / iPad.
Objective-C follows Object Oriented Programming Structure (OOPS) and Model-View-Controller (MVC) strongly.
OOPS in Objective-C take care of code implementation. All the interfaces are declared in .h (header) files and all its implementations are defined in .m (implementation) files.
So, if the developer needs to access any of the existing functions / behaviors, he never needs to create it from scratch. Instead tey can import .h file in their .m file and can proceed with the implementations.
Objective-C strongly follows MVC pattern. View which is responsible to display the users data, it gets the data from the model. Controller is the coding part which takes care of mapping view and model.
For example, we create a variable in .h class and modify the value in .m class.
In .xib file, we map the variable to a label object using File’s Owner property under Outlet section. This is how, class file (Controller) manages view and model mapping.
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