How to build a message borad(forum) using vb.net

Hi I need to kwon how to build a message board using vb.net 2005/2008. I know there a lot of free samples but i just want to know what happens behind so that i can expand my knowlegde on how this is accomplished. If there's any article,soruce code or link where i can learn how to do this i'll appreciate. Thanks

Donald Malunda