Do you want to try Linux or Mac OS or some software but a bit concerned about your existing operating system and other changes that may cause more issues, then you must try virtual machines. Virtual machines are emulation of a particular computer system. These programs allow you to run any operating system right from your windows or existing operating system. They act as virtual system where you can experiment almost anything without causing any harm.
This is specially beneficial to web developers like me when we have to test websites in various operating system and browsers. I have tried Linux (Ubuntu) and Mac OS Yosemite.