It is like a mini OS that you can boot as soon as you power on your computer (even before getting to the POST page) It comes with a web browser, media player, and a couple other things. This would be great on a laptop if you want to check your email real quick and then shut your computer off but since my desktop runs on 24/7 I have no need for it.
I could never get mine to work, I use a wireless network adapter and it will not load the driver for it. So it want find a connection, I have messed around with everything expect the internet feature. Like said before it would be handy on a netbook or laptop, although I would probably still rather use the new Google OS instead of using it.