what does the robex in hyudai’s mean?

I saw a few hyundai's for sale, and some said "Robex" So, I got to wondering what the difference was between some that said that, and others that did not. Specifically, I saw two 130 machines, one Robex, one not. Sorta sounds (I did some searching on here) that older hyundai's are not that good. Rodney