This comprehensive book is based on the Navier-Stokes and other continuum equations for fluids. It interprets the analytical and numerical solutions of the equations of fluid motion. Topics included are turbulence, and how, why, and where it occurs; mathematical apparatus used for the representation and study of turbulence; continuum equations used for the analysis of turbulence; ensemble, time, and space averages as they are applied to turbulent quantities; the closure problem of the averaged equations and possible closure schemes; Fourier analysis and the spectral form of the continuum equations, both averaged and unaveraged; nonlinear dynamics and chaos theory.