# Definition
$X$, $M$ then $f : X \to \mathbb{C}$ [[Measure|measure]] form an algebra under **pointwise** operations:
$$(f + g)(x) = f(x) + g(x)$$
$$(f \circ g)(x) = f(x) \times g(x)$$
# Example
$(f+g)(x) = f(x) + g(x)$
The plus part of this operation is the pointwise part