The paper by Eisenstein and Hu provides scaling relations and fitting formulae for adiabatic cold dark matter cosmologies that account for all baryon effects in the matter transfer function to better than 10% in the large-scale structure regime. The formulae are based on a physically motivated separation of the effects of acoustic oscillations, Compton drag, velocity overshoot, baryon infall, adiabatic damping, Silk damping, and cold dark matter growth suppression. The authors also present a simpler and more accurate form for the zero baryon transfer function. These descriptions are used to quantify the amplitude and location of baryonic features in linear theory. While baryonic oscillations are prominent if the baryon fraction Ω_b/Ω_0 ≥ Ω_0h^2 + 0.2, the main effect in more conventional cosmologies is a sharp suppression in the transfer function below the sound horizon. The paper discusses the phenomenology of these effects, including the location and amplitude of baryonic oscillations and the alteration to the intermediate-scale shape and small-scale normalization of the transfer function. The authors provide a fitting formula that approximates the full transfer function on all scales and discuss its performance. They also present a new fitting form for the zero-baryon limit that is more accurate on small scales than previous forms. The paper concludes with a discussion of the implications of these results for cosmological parameter estimation and the detection of baryonic features in future large-scale structure surveys.The paper by Eisenstein and Hu provides scaling relations and fitting formulae for adiabatic cold dark matter cosmologies that account for all baryon effects in the matter transfer function to better than 10% in the large-scale structure regime. The formulae are based on a physically motivated separation of the effects of acoustic oscillations, Compton drag, velocity overshoot, baryon infall, adiabatic damping, Silk damping, and cold dark matter growth suppression. The authors also present a simpler and more accurate form for the zero baryon transfer function. These descriptions are used to quantify the amplitude and location of baryonic features in linear theory. While baryonic oscillations are prominent if the baryon fraction Ω_b/Ω_0 ≥ Ω_0h^2 + 0.2, the main effect in more conventional cosmologies is a sharp suppression in the transfer function below the sound horizon. The paper discusses the phenomenology of these effects, including the location and amplitude of baryonic oscillations and the alteration to the intermediate-scale shape and small-scale normalization of the transfer function. The authors provide a fitting formula that approximates the full transfer function on all scales and discuss its performance. They also present a new fitting form for the zero-baryon limit that is more accurate on small scales than previous forms. The paper concludes with a discussion of the implications of these results for cosmological parameter estimation and the detection of baryonic features in future large-scale structure surveys.