\begin{definition}[Definition:Section (Topology)]
Let $M, E$ be topological spaces. 
Let $\pi: E \to M$ be a continuous surjection. 
Let $I_M: M \to M$ be the identity mapping on $M$. 
Then a '''section''' of $E$ is a continuous mapping $s: M \to E$ such that $\pi \circ s = I_M$.
\end{definition}