  Atomic electrons are sensitive to the properties of the nucleus they are
bound to, such as nuclear mass, charge distribution, spin, magnetization
distribution, or even excited level scheme. These nuclear parameters are
reflected in the atomic transition energies. A very precise determination of
atomic spectra may thus reveal information about the nucleus, otherwise hardly
accessible via nuclear physics experiments. This work reviews theoretical and
experimental aspects of the nuclear effects that can be identified in atomic
structure data. An introduction to the theory of isotope shifts and hyperfine
splitting of atomic spectra is given, together with an overview of the typical
experimental techniques used in high-precision atomic spectroscopy. More exotic
effects at the borderline between atomic and nuclear physics, such as parity
violation in atomic transitions due to the weak interaction, or nuclear
polarization and nuclear excitation by electron capture, are also addressed.
