''B'' Selection doesn't work

I have been following this tutorial http://www.youtube.com/watch?v=85kmzClDxn0.
Right from the start, i can’t select properly. When i do select, it just selects the front part of the cube (when i am in front view ). How do i select the edges (the ones i see and the ones at the back of the cube) ? Ask if you need screen shots to help me.

Thanks,
John

Either use wireframe view as used in the video


or disable ‘Limit Selection to Visible’


Thank you for the answer, but it wasn’t actually the problem.
I figured that out myself after a while. I need to select with '‘B’ then i need to hold right mouse button down and move.
I was doing that but on the edges i wanted to move, that just moved the front edge, not the back one.

Anyway, thanks for the quick response.
I will post my first project on the forum !