what will an unlock code for the samsung beat (t539) do?

ive heard alot about unlocking phones and all, while i was searching for interesting things to do with my brand new samsung beat from t mobile. ive seen several websites telling you how to unlock it and whatever, but what exactly will that do? could it damage my phone?
because im on a contract and got this phone for free, so if i mess it up im screwed. just tell me everything you know about the samsung beat and about unlocking phones. thanks.

i also have one more questoin, what is the Pc studio option on my phone?
when i choose what i want to happen when i plug in the usb there is media player, mass storage, and pc studio... what is that?
i just use mass storage and drag and drop to get music and video on and off.. is there an easier way?

The specialty in unlocking a Samsung T539 is that if we unlock it the user is able to switch networks, avoid data roaming, high resale value for the phone. Recently I unlocked mine using the unlock code from Wickedunlock.com and removed the network lock permanently.So if you want to enjoy the privilege of the unlock service you can visit the website that I have mentioned.I am not sure about the Pc Studio though....