Can I Reinstall Windows 10 Once I Upgrade?

[Corrine]

This is a question a lot of people have been wanting an answer to and now we have it.  The answer was provided by Microsoft employee and Forum Moderator at Can I reinstall Windows 10 once I upgrade?:

Yes. Once you upgrade to Windows 10 successfully using the free upgrade offer, you will be able to clean reinstall Windows 10 on the same device during and after the free upgrade offer period without having to purchase Windows 10 or having to go back to the prior version of Windows that you upgraded from.

[Corrine]

Also stated here by Sidd of Microsoft in reply to another question:

Not clear on what a "clean reinstall" is. So if I delete the OS partition on the hard drive and want to start all over with installing windows 10 from the bios mostly likely from a disc or usb drive.. will I be able to do that? Are we going to get a windows 10 ISO for later install like I have for my current windows OS?

Yes, it will be possible to download Windows media.