\begin{definition}[Definition:Integral Operator]
Let $X, Y$ be sets of mappings, real or complex numbers.
Let $A : X \to Y$ be a mapping such that $A$ is expressible as an integral of elements of $X$ (possibly involving weight functions and kernels).
Then $A$ is known as an '''integral operator'''.
Category:Definitions/Operator Theory
\end{definition}