G'day aviation1972, and Welcome to BC
A VirtualBox or VB is a software virtualization package that installs on an operating system as an application. VirtualBox allows additional operating systems to be installed on it, as a Guest OS, and run in a virtual environment.
I know it all sounds a bit spooky...but "virtual machines" are in common use. I use one myself. (Oracle VM VirtualBox Manager)
My main operating system is Linux. Because I spend quite a bit of time working on windows 10 machines, I also need access to a working, up to date copy of win 10. I installed win 10 inside a VM......easy to do...requires very little space....and works like a dream. And any time i wish to get rid of it...right click, select delete and its gone !
Uninstalling should not present any problems.
Why it was installed ?.....maybe to experiment with another operating system such as linux......?...or to run an old game or app that wont run in windows 10...(but used to run in win 7 or xp)....?
If i knew the age of the family member I could probably hazard a more accurate guess as to their intention....
I wouldnt lose any sleep over it.....in fact.....embrace it and have a second OS (operating system) on your PC
(I gave win 10 the 'flick' some time ago and have never looked back
The Linux Forum on BC
Condobloke ...Outback Australian fed up with Windows antics...??....LINUX IS THE ANSWER....I USE LINUX MINT 18.3 EXCLUSIVELY.
“A man travels the world in search of what he needs and returns home to find it."
It has been said that time heals all wounds. I don't agree. The wounds remain. Time - the mind, protecting its sanity - covers them with some scar tissue and the pain lessens, but it is never gone. Rose Kennedy