Every electric circuit is made up of three components which are the node, branch and loop. An electric circuit is combination of one or more networks in a close path which gives room for the flow of electric current.
Node in an Electric Circuit
A node in an electric circuit is defined as a point through which an electric circuit element is connected. It can be meaningfully referred to as a point where point where the terminal of two or more circuit elements are connected together. In other words, it is the junction points of two or more circuit elements. In the circuit below, the nodes are indicated with bullet points.
Branch in an Electric Circuit
A branch in an electric circuit is defined as a path between two nodes in a circuit where a circuit element (resistor, capacitor, galvanometer, etc.) is connected. A circuit element connected to an electric circuit in general has two terminals. When, one circuit element is connected to the circuit, it connects itself through both of its terminals, to be a part of a closed path. The branch of an electric circuit can be defined more precisely, as the portion of the circuit between two nodes which can deliver or absorb energy.
Loop in an Electric Circuit
A loop is any closed path of an electric circuit formed by branches. If an electric circuit after going through a set of nodes returns to same starting node without crossing any of the intermediate nodes twice, he has travels through one loop of the circuit.