Turbulent fluid dynamics are literally all around us. This video describes the fundamental characteristics of turbulence with several examples from nature and from engineering. We discuss how turbulent fluids are unsteady, three-dimensional, mixing, and multiscale. We also describe how the Reynolds number in the Navier-Stokes equations controls this complexity. Citable link for this video: https://doi.org/10.52843/cassyni.hrpvdf Check out the excellent notes by Lex Smits: http://profs.sci.univr.it/~zuccher/downloads/FD-MAE553-Smits.pdf @eigensteve on Twitter eigensteve.com databookuw.com