Does declaring a variable to be constant do anything at all?

No the two concepts are orthogonal. You shouldn’t describe mutating an object as binding. I’m not sure what background you have (i.e. what languages are you familiar with) but I’ll try and point out that variables are orthorgonal to object in julia, just like most scripting languages. This is unlike C++ for example, where variables basically equal objects. Immutable means, well, you can’t mutate an object. Constant global means you can’t change the object it’s pointing to.