**Warning
Before attempting to dual-boot Linux on an existing Windows computer it is essential to
backup all personal data to an external drive.
There are two main reasons why people may wish to dual-boot Windows and Linux:
1.) They are familiar with Windows and are perhaps interested in replacing it with Linux. They may be reluctant to ditch Windows completely, in case they do not get along with Linux 100% and so decide to keep a foot in both camps....