The early 2011 MacBook Pro has an update for Boot Camp that can be installed while running Windows. The update brings it to version 3.2 and solves a problem with “issues with shutdown” and fixes with “Japanese and Korean keyboards.”
Boot Camp is the system Apple users to make booting a Mac into the Windows operating system after it is installed. Another tool that can be used is Parallels or VMWare Fusion both of which lets a user run Windows on top of Mac OS X in a virtual environment. This allows users to run Windows programs within Mac OS X.
Boot Camp requires the user to reboot into Windows in a dual booting environment. Boot Camp only works with Intel based Macs. It comes with OS X so it is free to Mac owners. And it allows users to access their Mac partition so they can open files in Windows. For more about Boot Camp check out the Apple FAQ.