As new operating systems or versions of operating systems are released, there are times you may want to install them to see how you like them before you commit to overwriting your existing operating system. With a Windows PC, this is actually an easy task since Windows will setup a dual boot for you during the install process.
If you are planning a dual boot of any operating system such as Windows or Linux, make sure you first partition your drive or prepare a second drive for the install. In this way, you will ensure that your primary operating system is not affected by the install. Even though some versions of operating systems will perform a partitioning for you during the install process, I like to perform this process prior to installation by using a partitioning application. One that I found that is very effective is EASEUS Partition Master Home Edition. One of its best features is the price. The home edition is free for home use.
Once you have partitioned your drive, you can start the secondary operating system installation. Make sure you select the custom install option so that you can select a new installation in the partition that you just created. Once you have completed the install, when you reboot your machine, you should have a menu that lets you select either your original operating system or the new one you just installed. Now you can take your time learning the new operating system and installing your applications to check for compatibility issues. When you are satisfied that all of your applications run in the new system, you may find that you no longer require the old operating system. At that point, you can decide if you want to remove the original operating system partition and add the partition space to your new operating system. Your partition software can help you with this process.
Note: I always recommend backing up your system to DVDs or an external hard drive before repartitioning just in case something goes wrong during the partitioning process. If you are worried about this step, your hard drive is large enough that you can afford to keep the original operating system, and your new operating system is a version of Microsoft Windows, such as Windows 7, you can go into the system settings and set your new operating system as the primary, plus you can set the time for the menu to display on the screen down to zero so that your system boots directly into the new operating system. Then, at any time if you need to go back into your old operating system, just go back to system settings and set the menu display time back up to 5 or 10 seconds so that you can select your original operating system the next time you reboot your machine.
This is also a great way for a developer to test his software projects in different versions of an operating system or to develop software for several different operating systems without purchasing additional hardware. This is also a great way to try many of the Linux flavors that are available before you decide which one is best for you.