Endpoint

In graph theory, an endpoint ^[1] of an edge is one of the two vertices it joins. For an undirected edge $\{u,v\}$, both $u$ and $v$ are simply called endpoints. For a directed edge $(u,v)$, the two endpoints are distinguished by name as the tail $u$ and the head $v$.

Definition

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Definition 1 (Endpoint)

Let $e$ be an edge joining vertices $u$ and $v$. The vertices $u$ and $v$ are called the endpoints of $e$.

References

1. [1]

   “Glossary of graph theory”, Wikipedia, Available: https://en.wikipedia.org/wiki/Glossary_of_graph_theory, Accessed: 2026-07-15 ↩