Why Virtual box for Vagrant on Linux?

Question

linux

Hey!
I'm starting to get to know Vagrant. I read somewhere that if we use Windows or OS X, then VirtualBox is needed to create a virtual Linux OS. To take full advantage of the Linux system under win or os-x in virtual space. I understood it.
But the question arose why it is necessary to emulate (or create a virtual space) Linux under Linux?
Or have I misunderstood everything and in fact VirtualBox is a ''box'' for Vagrant, and Vagrant will not work without a ''box''?

Answer 1

https://www.vagrantup.com/docs/providers/
Virtual Box is not for Linux emulation, but for creating virtual machines, any and on any OS.
Those. VPSok/containers with a separate environment.