The package consists of a set of computer programs for calculation of energy levels, radiative transition wavelengths and probabilities, electron impact excitation and photoionization cross sections, etc. The programs were originally written by Robert D. Cowan in 1962-1991 (see R.D. Cowan, The theory of atomic structure and spectra, University of California Press, Berkeley - Los Angeles - London, 1981). The dataset was updated in November, 2021.