When in Wireframe mode and selecting an egde, only the top is selected and not the whole vertices I am watching this Blender tutorial, where switches to Wireframe viewport shading mode with Z, and he mentions when clicking it should select the whole vertices

https://youtu.be/6FuvpwZeXfw?t=2m12s

But when I turn on transparency, and select an edge, only the edge I clicked is selected not the whole side

https://i.gyazo.com/5bbfe7e209b5b52ab70f78004a3e34ef.mp4

How can I selected the whole side like this?
In the video (at 2m16s) he forgot to mention that just before selecting the vertice he is pressing the C key, C for Circle select.



He explains about C for Circle select at 2m30s as he is selecting the next corner vertice.