Robin2:
Just out of curiorsity does Windows run inside VirtualBox or does VirtualBox run inside Windows? Or, put another way, does one install VirtualBox on a blank hard disk and then install Windows and Linux etc?Also, out of curiosity, doesn't the use of VirtualBox (or equivalent) use up a significant amount of the PC's performance before any OS gets a look in?
I have been thinking about something like this but I have never tried it.
...R
VirtualBox is an application that runs in Windows, or Linux, or Mac. Whatever system you run it on is called the Host. You then launch it and create Guest computers and spin them up. For a Guest you select the type and sizes of drives, memory, number of processors, processor features, network cards, and all that jazz. All that stuff is stored in files and is emulated when you "boot" the guest computer. You boot the guest computer by clicking a button. You can run whatever OS you want on your guest computers. The only limitation is Mac OSX guest computers are only allowed if the host computer is also Mac OSX.
Since most performance has to do with memory, and most modern computers (less than a dozen years old) have plenty of memory, the guest runs with quite acceptable performance for most applications.
You can do fancy stuff, such as running the guest OS seamless, which makes the guest OS applications run side-by-side with your host OS apps, which is pretty cool. You can also run guests by launching them on the command line in the background or as a scheduled task, and run them "headless" which means they are completely hidden in your host machine and you can't even tell they are running. But they can be doing tasks for you, such as running web, ftp, media, or other servers. You can then remote control the guest with something like remote desktop or VNC when you need access to the screen.
I use this virtualization technology because it is fun, free, and handy, but I don't keep up with the razor's edge of developments. I understand some virtualization hosts run on bare metal, which means there is no host OS. The virtualization software runs as the main OS, and then you create guests for all of your various OS's. I have not messed with that. VMware is another major brand of virtual server, and Microsoft also has one but I don't know the name of it. I have been using VirtualBox for years. It was made by Sun Microsystems, and Sun was purchased by Oracle a few years back, so it is now Oracle software. Oracle also has a Linux distribution, which is free and it is configurable as pretty much an exact copy of Redhat (Redhat is not free).