Graph theory!!!

Graph theory is a prime study area comming under discrete mathematics.This is mainly used to solve a wide range of practical problems in our day to day life dealing with both natural & manmade structures.Here the entities are represented by means of points and the  relations or connections are denoted by using line segments.Several segments meets at a point forming nodes or vertices.

Graphs can be directed or undirected.In directed graph (digraph)the direction of the  flow of entities is shown with the help of arrows and in undirected graph there is no such notations.Also its possible to give weights to each segments depending upon the revelence of each segment with respect to other and is called as weighted graphs.