In this article we give an overview of the developments in the field of
spectral classification and its continued importance in the fields of stellar
and galactic evolution. The extension of MK system to cool stars as well as
refined classification of the hot stars using the new data obtained from modern
ground based facilities and space missions has been described. A brief summary
of automated methods of spectral classifications developed for the quick and
objective classification of the ongoing and future surveys is presented. A new
spectral class encoding system developed for exploitation of databases is
described. Recent large scale spectral classification catalogues are listed.Comment: To appear in BASI, 33 pages, 9 figure