language question

Is anyone familiar with Reason? It is a music software program that affords the user a virtual music studio...the actually program looks great...very elegant...My main question is: what type of computer language was used in making this program...I have always been interested in learning how this is done but not sure where to start.....check out http://www.propellerheads.se/ THanx!

also...i am really only concerned with how the actual APPEARance of such a program like Reason was created:(NOT the underlying program that exploits the hardware-motherboard, audio input-output, ya' know? )...Thnk you again!