What is HarddiskVolumeShadowCopy?

Keep noticing HarddiskVolumeShadowCopy## in my system drive, but google search doesn't really turn up an explanation. What is it? The latest showed as 85gb, though that's hard to believe. I noticed it today because Comodo found 751 items of malware, all in Comodo's quarantine in HarddiskVolumeShadowCopy.

This is single user system, 8.1 x64 Pro. If it has to do with backup, I'm not running Windows backup anymore because as far as I can tell it no longer exists as it did in 8.0. Plus, I didn't back up on the system drive (C). Strange thing, however, is until I turned Action Center reporting off for backup, I was getting a message about backup having completed and did I want to see what couldn't be copied. Thanks,

This is a wiki explaining it all , but it's basically a way for the system to backup/update/fast restore your system bypassing any open/in-use files , the backup copies all the files (even ones in use) and then runs/works on the backup from that image instead.
Shadow Copy - Wikipedia, the free encyclopedia

That wiki entry says the following:
"On Windows 8 and Windows Server 2012 persistent shadow copies are no longer available. Therefore the ability to browse, search and/or recover older versions of files via the Previous Versions tab of the Properties dialog of files was removed for local volumes."

So if not Win 8 why am I getting it? I do create frequent restore points, so is that it? The wiki says one can choose where to store them, but I don't see that under Sys Restore (Recovery) in the CP.