\textbf{Left:} Al 'Surfer' Einstein  excited about gravitational waves (adapted from a Mark Summers artwork). \textbf{Right:} The first gravitational waves signal detected by humankind. Data from the Washington (Top) and Hanford (middle) detectors are compared to the expected theoretical signal from two merging black holes. The two detected signals are compared after being shifted by about 7 ms in the bottom panel (the small delay between the two signals is due to the finite speed of the gravitational waves, which move at the speed of light).