How to create a menu for bootcamping at startup

I boot camped my mac and so did the college I attend. They have a system that lets us choose what start-up disc you want to boot on without pressing any option key or setting the start-up disc from system preferences. Once restart it goes straight to a menu that there lets you choose Windows or Mac. How can I do this. Is this a system in my mac, third-party software, mac software? Any help is appreciated.