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Magic. That doesn't mean you'll likely find it preferable to do all your programming without variables. It does mean that variables aren't at all necessary. Variables are human bookkeeping labels/tags, to help our feeble memories cope. Useful sometimes, a huge PITA other times - think assembler, C, etc., where pretty much every bit of program requires a variable. __ Yes, all of that is OT. What's not OT is that for Emacs users, _in particular_, special (global) vars can be quite useful. Precisely _because_ they can let you reach across existing code without modifying it, as far as you like, and change behavior. And still have some control over extent etc. Dynamic binding is yet another story of power being usable for good & bad. Be careful how you use it; know why you use it. RMS summarized the use cases 42 years ago - still 100% relevant today: https://www.gnu.org/software/emacs/emacs-paper.html#SEC15 ___ SKI etc.: https://en.wikipedia.org/wiki/Combinatory_logic 42: https://en.wikipedia.org/wiki/The_Hitchhiker%27s_Guide_to_the_Galaxy#42,_or= _The_Answer_to_the_Ultimate_Question_of_Life,_The_Universe,_and_Everything https://en.wikipedia.org/wiki/Jackie_Robinson