Goophone S4 Mega Questions...

I was pondering this; the overseas replica Goophone of the Samsung Galaxy S4 claims to be "unlocked" and thus works with GSM and WCDMA, but what does this mean? I guess I'm wondering if this means it will work with straighttalk sim cars or tracfone sims, something along those lines. Also, does the data still function. I'm no phone guru so any advice would help!!!!! Thx.

via Cell Phone Forums (French) http://cellphoneforums.net/fr/general-cell-phone-forum/t363575-goophone-s4-mega-questions.html