\begin{definition}[Definition:Evaluation Mapping]
Let $S, T$ be sets, and let $S^T$ be the set of all mappings from $T$ to $S$.
The '''evaluation mapping for $S^T$''' is the mapping $\operatorname{ev}: S^T \times T \to S$ defined by:
:$\operatorname{ev} \left({f, t}\right) := f \left({t}\right)$
\end{definition}