VirtualBox is a software application that can help many people when it comes to using programs designed for one operating system while working on another. In that situation, the best option is virtualization, in other words, to launch one operating system inside another, and VirtualBox can do that perfectly.
Virtualization software for Linux
Once you have installed VirtualBox, using a virtual machine to launch another operating system is really easy. Thus, unless it's impossible due to the hardware, you'll be able to launch Windows inside Linux. This software is compatible with all the Windows OS that have been launched since 98: Windows Vista, 2000, XP, Server 2003, NT,... Likewise, you'll be able to try out other Linux distributions without having to install them.
Furthermore, VirtualBox includes some improvements that make life easier for the user, like USB controllers that can be told that one of the PC's real USB connections has to act as a virtual machine. There are also plug-ins that improve the performance at specific moments.