Graph: Directed vs. Undirected
- Distinguish between directed vs. undirected graph.
There are different kinds of graphs! Two broad categories are directed vs. undirected graphs.
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The difference is in the type of edge they have.
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For example, $A$ and $B$ may represent two bus stops. Therefore, the directed edge shows one-way traffic from stop $A$ to stop $B$.
On the other hand, $A$ and $B$ may represent two individuals on Facebook. The undirected edge represents the friendship between them.