CIRCUIT ANALYSIS AND TECHNIQUES
Essential nodes and essential branches

In addition to the terminology above, it is useful to introduce the concept of essential nodes and essential branches.

Essential node is a node joining three or more elements.

Essential branch is a path that connects essential nodes without passing through an essential node.

In case of a circuit analysis requirement, only essential nodes and essential branches must be taken into account.

On the above circuit there are 4 essential nodes (b,c,e,g), and on the figure below the 7 essential branches of the circuit are shown: