Radii for most stable nuclei have been deduced from electron scattering form factors and/or from the x-ray transition energies of muonic atoms. The relative radii for a series of isotopes can be extracted from the isotope shifts of atomic x-ray transitions. The rms radius for the nuclear point-proton density, \( R_p \) is obtained from the rms charge radius by: $$ R_p = \sqrt{R^2_{\mathrm{ch}}- R^2_{\mathrm{corr}}}, $$ where $$ R^2_{\mathrm{corr}}= R^2_{\mathrm{op}}+(N/Z)R^2_{\mathrm{on}}+R^2_{\mathrm{rel}}, $$ where $$ R_{\mathrm{op}}= 0.875(7) \mathrm{fm}. $$ is the rms radius of the proton, \( R^2_{\mathrm{on}} = 0.116(2) \) $\mbox{fm}^{2}$ is the mean-square radius of the neutron and \( R^2_{\mathrm{rel}} = 0.033 \) $\mbox{fm}^{2}$ is the relativistic Darwin-Foldy correction. There are additional smaller nucleus-dependent corrections.