When I was little we would always play this game with the jump rope we would call "snake". Two people would hold either end and kneel at the ground and wiggle the rope parallel to the ground causing waves to be going back and forth on the ground. And the object of the game is to jump over the jump rope without the "snake" getting you. First you would start off small, with little amplitudes. An amplitude is measured from the baseline to the top or bottom of the wave. And as the game progresses the snake would create bigger and higher amplitudes to make if more difficult to jump over the snake. And since there is friction on the ground, the poeple holding the rope need to go fast with a high frequency to make the waves actually appear on the ground. I thought I would share this game that I played when I was little and who knew that waves would be involved.