The initial reference wave is a simple sine wave starting in a downward direction. You can add one, two, or three more sine waves to the reference wave. You can change the amplitude ("height"), frequency ("speed"), & phase ("starting position", measured in radians) of each of the additional waves by entering values in the appropriate boxes at the top of the screen, then clicking on "Draw Combined Wave". For the Reference Wave, Amplitude = 1, Frequency = 1, & Phase = 0. Click "Draw Reference Wave" to see where you're starting, then experiment with different parameter values. Click "Draw Test Wave (1, 2, or 3)" to see the sine wave #1, 2, or 3 that you're going to add to the reference wave. The individual waves will be pretty boring, but strange things happen when they are added. Some interesting places to start:

This last example looks like a good approximation of a daily log of stock market activity.

If you get tired of entering new parameters, click on "Random", then "Draw Combined Wave". Most of the time, the reult looks like noise, but occasionally, something more interesting appears.