What is the difference between “/private/var/vm” and “/vm”?

I’m wondering why my Mac (running macOS High Sierra 10.13.6) has both /private/var/vm and /vm:

$   ls -l /private/var/vm /vm /private/var/vm: total 4194304 -rw------T  1 root  wheel  1073741824 May 17 19:12 sleepimage -rw-------  1 root  wheel  1073741824 May 26 13:29 swapfile0  /vm: total 2097152 -rw-------  1 root  wheel  1073741824 May 14 23:49 swapfile0 

I know these have to do with virtual memory, but why are there two of them; what’s the difference?

Are both of the files named swapfile0 being used or can I delete one? I assume that if I would delete one, it would be the second one, as it hasn’t been modified in over a week, whereas the first one was modified only a few minutes ago (I rebooted my Mac just now). But how can I tell for sure whether it is safe to delete? Why does it exist to begin with?