Create a folder on your harddrive and call it \DATA or \MyStuff, etc. It doesn't matter.
That's still good advice, but I agree that it needs to be on a different physical Drive.
I have a partition on a 2nd HD for all of my general data.
I also have a Music Data partition/drive with folders for each of my BiaB/RB and other song files.
My backup system is a weekly batch file which copies all of these files to a dated folder on an external USB drive AND a local Hard Drive,
Along with a 2nd daily batch file that only copies files which have changed.
The suggestions about rotating your USB drives, off-site and cloud storage, are also valuable.
There is a classic story about a guy who had been working on his Doctrinal Thesis for 5 years.
He had multiple backups of everything, but his house burned down along with all of his backups.
I'll post my batch files if anyone is interested.
It took me a while to find out how to do the Date - Name Folders