Yes. The Wikipedia article is to be honest, crap. RPL is a functional stack based language sort of like lisp and forth combined with mathematica thrown in for good measure.

Its both compiled and interpreted and a system language and a user language. Couple of examples:

'X=Y^2' 'Y' SOLVE 149 'X' STO EVAL @evaluate first expr for Y=149 .. Including optimising it by rearranging it

{ "a" "b" "c" } SORT REVLIST << "M" + >> MAP @sort then reverse then add M string to every list item using anonymous function and map.

Storage is entirely transparent and persistent as well.

Quite my favourite language these days. I can actually do real work with it and it runs in my pocket on a 75MHz ARM (which is more than enough for it), has built in context sensitive help, a debugger that even puts gdb to shame and has 2Gb of persistent storage and lasts a month on 4 NiMh eneloop AAA's. All for £79 :)

It also doesn't have any distractions like the internet.