What to use?
The main problem with class inheritance is that there is a side effect when inheriting a class from another. Every sub-class inherits properties and methods from the parent class. As mentioned above, this can quickly lead to huge problems if not used properly. This is where the age-old design pattern of composition over inheritance comes into the picture.
When people say prefer composition over inheritance, they are referring to class inheritance. There are a lot of flaws with class-based inheritance, but not all inheritance has these issues. Composition in JavaScript is implemented through concatenative inheritance-- wait, what is that?
