Attach a Vertical Framing Member

What happens here

Next, a vertical piece of dimensional lumber is cut and fitted into position, perpendicular to the previously installed horizontal member and against another existing vertical frame. This piece acts as a short stud or a cripple stud, forming a corner or a vertical division within the small framed section. It is then rapidly fastened into place using the pneumatic nailer.

Goal: Form a corner or vertical division with a stud-like member.