An analysis of the hydraulic jump and the influence of friction forces on energy dissipation through the hydraulic jump is presented. The geometry of different types of hydraulic jumps (with Froude numbers ranging from 2.0 to 13.5) is measured and compared to the classical theoretical values. Theoretical values are found to overestimate the sequent depth and to underestimate the energy dissipated through the hydraulic jump, due to the fact that theory ignores friction losses. Finally, new expressions considering friction forces are introduced for predicting sequent depths and energy dissipation of the hydraulic jump.