a platform is any hardware or software used to host an application or service. An application platform, for example, consists of hardware, an operating system and coordinating programs that use the instruction set for a particular processor or microprocessor. In this case, the platform creates a foundation that ensures object code will execute successfully.
Virtual machines allow you to run one operating system emulated within another operating system. Your primary OS
VirtualBox has cross-platform support, and a huge number of features that make running and maintaining virtual machines a breeze. Virtual machine descriptions and parameters are stored entirely in plain-text XML files for easy portability and easy folder sharing. Its "Guest Additions" feature, available for Windows, Linux, and Solaris virtual machines, makes VirtualBox user friendly, allowing you to install software on the virtual machine that grants extra privileges to the host machine for tasks like sharing files, sharing drives and peripherals, and more.
Running multiple operating systems side-by-side gives you the chance to test applications, run platform-specific software, and tons more without ever rebooting. It's also extremely cool. Here's how to run Windows, Mac, and Linux simultaneously and pain-free as possible.