Interface? Network?

I have been looking up different definitions of the term ‘interface’, roughly narrowing it down to a point of interconnection between entities. Yet, an interesting point is that most definitions seem to list it as an interconnection between two entities. Can interface occur on a larger scale and take place between more than two things, or is that a network containing many individual points of interface?
In a conversation between a group of people, whether it be face to face or online, they are interfacing on a plane where one individual can speak forth something to the group as a whole which can in turn be answered by any or all of its other members. Is this a network of communication with multiple points of interface or an example of interface between many entities?
On the human/machine relation scale, I can interface with a keyboard and screen at the same time (as I am now), in this way there is interconnection between more than two entities where I am interfacing with them all at the same time. Yet are ‘we’ also networking? Where does one end and the other begin? Are they different or essentially the same… ?