Backing up Windows 8

My laptop came with Windows 8 pre-installed and I want to make a backup of it in case it crashes. I have a 1 TB external USB HDD. Can I use it for both making a backup of Windows and then continue using same drive to make auto backups of my PC per request. Or do I have to have separate memory devices, i.e., one that only contains a backup of windows and one for other backups. Just wondering before I do any backing up because if I backup Windows on my 1 TB drive and the rest gets blocked for other saves then that would be a waste of good memory space..,

You can use the same drive. I would recommend using Macrium Reflect Free Edition to do the backup though.

Good advice, Reflect will work in case of a drive failure