The reason why it's interesting is it is basically a grammer for editing text. It's simple enough that you can easily create new strings of grammar which do wha

The reason why it's interesting is it is basically a grammer for editing text. It's simple enough that you can easily create new strings of grammar which do what you want but powerful enough that the skill ceiling is practically infinite. Once you have a grammar for editing text a lot of interesting features fall into place quite naturally like having 'undo trees' instead of just linear undo, being able to write complex macros in the same language you edit text in, etc...