In mathematics, the graph of a function is the set of ordered pairs , where In the common case where and are real numbers, these pairs are Cartesian coordinates of points in a plane and often form a curve.The graphical representation of the graph of a function is also known as a plot.
In the case of functions of two variables – that is, functions whose domain consists of pairs –, the graph usually refers to the set of ordered triples where . This is a subset of three-dimensional space; for a continuous real-valued function of two real variables, its graph forms a surface, which can be visualized as a surface plot.