Can someone help me .

I am trying to model some guns. But in edit mode when I select vertex it's only selected one side (the side wich I can see) but there is no way to select the other . I select one vertex and it only move that vertex and I won't do vertex by vertex. Help pls!

Thnx for reading. It will ne more easy for me to figure it out if u use some pictures or detailed text explanation.

Thnx

http://www.blender.org/forum/viewtopic.php?t=21568