Classes are a very important part of object oriented programming. A class is the blueprint for any object in an object-oriented programming language. It encapsulates variables and methods related to an object, and a program creates instances of objects to work with. We can discuss specifics about classes in a later post, but for now, I wanted to talk a little about header files. Classes in Objective-C are comprised of 2 files, the implementation file, and a header file. What is a header file you may ask? Keep reading and you will learn, and even if you do know, there might be some useful history you may not know.