i) Node: A point or junction where two or more elements of the network are connected together is called as node.
ii) Branch: A part of an electric network which lies between two junctions or nodes is known as branch.
iii) Loop: Any closed path in an electric circuit where each element or branch is traversed only once.
iv) Mesh: A set of branches forming a closed path (same as loop) in an electric circuit. OR A loop that does not contain any other loop inside