Both pictures in # 1 are parallel connections.
What you are asking about concerns the so-called can and boxless installations.
A boxless installation is one in which there are no upper junction boxes, but this function is performed by deep boxes in which the sockets are mounted.
Branches are made with connectors placed at the bottom of the box, although some bunglers use socket clamps for this.
PS. The most important wire is missing from both pictures.