\begin{definition}[Definition:Loop (Topology)]
Let $T = \struct {S, \tau}$ be a topological space.
Let $\gamma: \closedint 0 1 \to S$ be a path in $T$.
$\gamma$ is a '''loop (in $T$)''' {{iff}}:
:$\map \gamma 0 = \map \gamma 1$
\end{definition}