Objective-C Recipes
Classes in Objective-C need interface and implementation definitions. Although
it’s not absolutely required, you typically keep the interface and implementations
in separate files. The file with the interface is named as same as the class itself
but with the .h file extension. The file with the implementation also has the class
name but with the .m file extension.
To use a custom class, you must import the class header file into the code file
where you intend on using the class. Then you can instantiate an object from the
class to use the functionality encapsulated in the class....
