Relativistic and quantum electrodynamic effects in highly‐charged ions

Recent spectroscopic data clearly indicate that both relativistic and quantum electrodynamic (QED) effects are indispensable in understanding the spectra of highly‐charged ions. QED effects are discernible even in spectra involving M‐ and N‐shell electrons. Current understanding and theoretical capability in predicting relativistic and QED corrections in atomic structure are reviewed.