Definition:Directed Graph/Arc

Definition
Let $G = \left({V, E}\right)$ be a digraph.

The arcs are the elements of $E$.

Informally, an arc is a line that joins one vertex to another.

If $e \in E$ is an arc joining the vertex $u$ to the vertex $v$, it is denoted $uv$.

$u$ and $v$ are called the endvertices of $e$.