Differential inheritance

Differential inheritance is a common inheritance model used by prototype-based programming languages such as JavaScript, Io and NewtonScript.

It operates on the principle that most objects are derived from other, more general objects, and only differ in a few small aspects; while usually maintaining a list of pointers internally to other objects which the object differs from.

To think of differential inheritance, you think in terms of what is different.

Now Dumbo is a lot shorter, has big ears, no tusks, a little pink bow and can fly.

Using this method, you don't need to go on and on about what makes up an elephant, you only need to describe the differences; anything not explicitly different can be safely assumed to be the same.