Unity does a lot of things: it manages objects, renders them, animates them, calculates physics, and more. Unity itself is a program. The internal Unity code is accessible by you, the game developer, through the Unity point-and-click Editor interface we've already been using. Within the Unity Editor, scripts are manifested as configurable components. But, it's also more directly accessible by you through the Unity scripting API.
API, or application programming interface, simply refers to published software functions that you can access from your own scripts. Unity's API is very rich and nicely designed. That's one reason people have written amazing plugin add-ons for Unity.
There are many programming ...
