What language was Diablo written in?

I really love Diablo (the first one, the second ruined the franchise but getting rid of the atmosphere and making it about collecting items as currency) and want to know what language it was written in. Also, I'm currently playing on US East if anyone wants to play with me.

I really wish Blizzard would fix the fucking hacking though. It should take them a single engineer to do it at this point.

>>3
I'm actually talking more about hacking character's stats and items. Also even back then people used to attack in town and do crazy damage. It was ridiculous.