About Lisp so far.
I've believe that everything I type into the REPL, is basically a pointer, either a pointer to a function, or a pointer to data.
So the REPL manages these pointers "invisibly" without my having to declare anything as a pointer specifically.
It's also probably why it can pass functions into functions; it's really just passing a function pointer.
Anyhow, that's how I think about it. Probably wrong, but that's what I'm working with as a mental model at the moment.
Linux geeks doing what Linux geeks do...