As we learned in an article on functions, the standard "correspondence rule" is a connection between a dependent variable $(Y)$ and an independent variable $(X)$.

**By means of a graph or drawing, which gives a visual aspect to the concept of the function. From the graph it is possible to understand whether it is a linear function (straight line), a quadratic function (parabola) and more.**

Remember that when it comes to a graphical representation of a function, each point in the domain $X$ will always have only one point within the range $Y$. Therefore, not every drawing is a graphical representation of a function. Here is an example.