Its completely different, WINE just installs DLL's into linux so...

Its completely different, WINE just installs DLL's into linux so you can run some windows apps, Virtual box creates virtual comptuers you can install OS's in.. its valled Virtualisation, in the old days companies would buy a physical server for each copy of windows or unix based OS... now they just buy a computer with lots of CPU's and say 512GB of ram in it, then run a hypervisor which splits the computer up into dozens of virtual comptuers.

this saves space, power, and colling needs as you can fit a few hundred servers in the space of 3 or 4 computers..

Virtual box gives you this virtualisation on your desktop.. so you can create a virutal computer, and run it in a window or go full screen, and the OS is not aware that it is running ontop of another operating system.

This is better than Wine because it is windows so will run everything.

You can install Virtual box on windows, linux, solaris and MAC OSX.