Konrad Hinsen has an interesting post positing that Emacs is one of the few pieces of malleable software extant in the modern software environment. To understand what that means, you should first read the definition of malleable that Hinsen links to. When I read it, I was struck by how similar it is to the GPL except that, like Emacs, malleable software should contain a built-in method of changing the software to your liking. The idea, as with the GPL is that users should be a able to adjust their software to fit their workflows.
Hinsen says that in the 70s and 80s, malleability was a common design goal but that only Emacs has any real traction today. His post considers why this is and contrasts Emacs with Smalltalk, another piece of software designed with malleability in mind. The difference, he says, is that Emacs is useful out of the box for the end user, while Smalltalk—which is, in some ways, more malleable than Emacs—is useful for developers but not much use at all for an end user.
Thinking of Emacs’ advantages in terms of malleability is a useful viewpoint. On the one hand, it’s really no different from what we always say but on the other, it gives us a framework for understanding why those advantages are advantages and matter so much.
Again, be sure to read the definition of malleability. You can’t really understand the post without it and it is, in some ways, the most interesting part of the post. This is a useful post if you want to understand what makes Emacs so special.