[ACCEPTED]-What is the difference between a directed and undirected graph-graph

It means exactly what it sounds like. In 12 a directed graph, direction matters. i.e. edge 11 2->3 means that edge is directed. There 10 is only an edge from 2 to 3 and no edge 9 from 3 to 2. Therefore you can go from vertex 8 2 to vertex 3 but not from 3 to 2.

In undirected 7 graph 2-3 means the edge has no direction, i.e. 2-3 6 means you can go both from 2 to 3 and 3 5 to 2.

Note that in the representation of 4 your graph, if you are using an adjacency 3 matrix, directed 2->3 means adj[2][3]=true 2 but adj[3][2]=false. In undirected it means 1 adj[2][3]=adj[3][2]=true.

The difference is the same as between one 6 directional and bidirectional streets - in 5 directed graph, the direction matters and 4 you can't use the edge in the other direction. An 3 undirected graph can be simulated using 2 a directed graph by using pairs of edges 1 in both directions.

All of the answers so far are right. Typically, a 16 graph is depicted in diagrammatic form as 15 a set of dots for the vertices, joined by 14 lines or curves for the edges. The edges 13 may be directed (asymmetric) or undirected 12 (symmetric).

Imagine if the vertices represent 11 people at a party. If there is an edge between 10 the two people if they shake hands, then 9 this is an undirected graph, because if 8 person A shook hands with person B, then 7 person B also shook hands with person A.

On 6 the other hand, if the vertices represent 5 people at a party, and there is an edge 4 from person A to person B when person A 3 knows of person B, then this graph is directed, because 2 knowing of someone is not necessarily a 1 symmetric relation.

Imagine graphs as a set of pumps( the circles) which 7 can send liquid to others when are connected.In 6 directed graphs the arrow show from where 5 it comes and where the liquid (data) goes 4 and in undirected graph it goes from both 3 ways.Also a directed graph can have multiple 2 arrows between two vertices(the pumps ) depending 1 always on the graph.

A graph in which every edge is directed 3 is called a Directed graph, and a graph 2 in which every edge is undirected is called 1 undirected graph.

In a directed graph, there is direction 7 but in un-directed graph there is no direction.

Think 6 in in terms of city network , where City A-> City B represents 5 one way from City A to City B which means 4 you can travel from City A to City B (may 3 be through this path). It's an example of 2 directed graph City c - City D represents the un-directed 1 graph where you can travel in any direction

A directed graph is a graph in which edges 11 have orientation (given by the arrowhead). This 10 means that an edge (u, v) is not identical 9 to edge (v, u). An example could be nodes 8 representing people and edges as a gift 7 from one person to another.

An undirected 6 graph is a graph in which edges don't have 5 orientation (no arrowhead). This means that 4 an edge (u, v) is identical to edge (v, u). An 3 example for this type of graph could be 2 nodes representing cities and edges representing 1 roads between cities.