This review article focuses on the understanding of turbulent Rayleigh-Bénard convection, particularly on how the Nusselt number (Nu) and Reynolds number (Re) depend on the Rayleigh number (Ra) and Prandtl number (Pr). It also addresses the scaling of thermal and kinetic boundary layer thicknesses with Ra and Pr, non-Oberbeck-Boussinesq effects, and the dynamics of large-scale convection rolls. The authors discuss experimental and numerical results, as well as theoretical models, to provide a comprehensive overview of the field. They highlight the challenges in predicting Nu and Re, the role of boundary layers, and the potential existence of an asymptotic regime at very large Ra. The review concludes with a list of future research directions.This review article focuses on the understanding of turbulent Rayleigh-Bénard convection, particularly on how the Nusselt number (Nu) and Reynolds number (Re) depend on the Rayleigh number (Ra) and Prandtl number (Pr). It also addresses the scaling of thermal and kinetic boundary layer thicknesses with Ra and Pr, non-Oberbeck-Boussinesq effects, and the dynamics of large-scale convection rolls. The authors discuss experimental and numerical results, as well as theoretical models, to provide a comprehensive overview of the field. They highlight the challenges in predicting Nu and Re, the role of boundary layers, and the potential existence of an asymptotic regime at very large Ra. The review concludes with a list of future research directions.