This Demonstration shows the functions for values of that run from 1 to the maximum frequency in steps of size in the bottom plot and their sum in the top plot This illustrates an approximation of standard waves sawtooth square etc by adding sine waves Fourier method Adding 30 waves with step size the graph of the sum approximates a sawtooth curve With 30 waves and step size the graph of the sum approximates a square wave With 15 waves and step size In general for the step size The step size parameter gives interesting artificial waves such as natural harmonics