I've mentioned it, like, a million times already, but here I go again, MooTools is an object-oriented web application framework. And what's OOP without classes? Not OOP, that's for sure! MooTools is, to me, the only JavaScript library that effectively implements and promotes the use of classes.
A class, in terms of object-oriented programming, is a definition of an object, or an object's blueprint, its design, its structure, its template, I can go on, but I think you get the picture. Classes are best described in real-world terms.
Let's say our class is "Dog". A dog can have a lot of traits, such as its name, its type (for example, Golden Retriever or Poodle), its age, and so on. In MooTools, these traits are called options, which is an object that contains default key/value pairs specific to a particular class.
A dog can also do a lot of things, such as bark, sit, or eat. In the context of JavaScript and classes, these are...