We live in a highly connected world! World Wide Web, social networks, brain networks, Railway networks, Power Distribution networks etc. are all examples of connections or say networks. All these networks can be pictorially represented as a collection of connected objects. Varied it may seem but all these networks have two common entities: nodes and edges. Here, a node is an object and an edge is a line that links objects together. In the case of a social network, the nodes are human profiles and the edges can be considered as following/ follower relationships between two profiles. Similarly, in the case of railway networks- stations are nodes and the railway lines that connect the stations are edges.