Bumpity Bump... =)

Can anyone tell me what vsync does?
I assume it was the refresh rate of the monitor
but mabey im wrong on that, anyhow just wondering why when sometimes im only rendering 2 or 4 polys I have a vsync ms. time of 8 or 10.. Sumthin seems strange about that to me..

Any help would be great..
Thanks

Homey