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Virtual machines allow you to run one operating system "inside of" another. The major advantage to using this method is that it does not require the user to reboot when they want to change the operating system they are using . The disadvantage is that since you are running two operating systems simultaneously your computer's resources are split, there is also an extra piece of software to buy so it is more expensive as well. Below are links to two popular virtualization programs. An important thing to know about these programs is that they require a separate purchase of Windows in addition to your purchase of their software. Neither piece of software will work unless you have a license to install Windows. Oracle also has a product called Virtual Box
Manually Partition and Install Multiple Operating Systems
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