One question I see a lot has to do with the mysterious “vshost” application that appears when you build your application. If you’re writing foo.exe, you’ll notice that there’s a foo.vshost.exe that gets produced and is running while you’re working in the editor. What is it? Dave Templin, VB lead for deployment, tells you all about it…
check the link
http://msdn2.microsoft.com/en-us/library/ms185331.aspx