I don't understand it either. I suspect the author does not know Lisp, and badly misunderstood an explanation from someone who does. I think that Lisp doesn't

I don't understand it either. I suspect the author does not know Lisp, and badly misunderstood an explanation from someone who does. I think that Lisp doesn't even fit well into that table, since putting LET in the first column would implicitly bring in declaration as well, much of the time SET in the second column would be misleading since mutation is so often done implicitly by a looping construct like DO, DOLIST, DOTIMES or whatever (no SET in sight), and there are all sorts of equality tests one could use. Edit: ok, I see the author has both updated it, and is specifically talking about Lisp 1.5 which does not have the looping constructs. On the other hand, it at least has a bunch of alternatives to SET that probably should be listed as well, like RPLACA, RPLACD, ATTRIB, and so on. I think that even in Lisp 1.5 variables could be declared in different ways to using LET (like rebinding a variable passed in to a function, so the assignment was in invocation).