SIMBAD is the reference database for identification and bibliography of astronomical objects. It contains identifications, 'basic data', bibliography, and selected observational measurements for several million astronomical objects. Developed and maintained by CDS, Strasbourg, SIMBAD is built with contributions from various institutes. It includes catalogues and tables selected for optimal multi-wavelength coverage and research support. The database is updated daily through collaboration with bibliographers. A WWW interface is available at http://simbad.u-strasbg.fr/Simbad. SIMBAD contains information for over 2.7 million astronomical objects, including stars, galaxies, and non-stellar objects. It includes cross-identifications from 4500 catalogues and tables, observational data from 25 types of data catalogues, and a bibliographic survey covering astronomical literature since 1950 for stars and since 1983 for extragalactic objects. The database is organized per astronomical object, providing users with all published information about any given object. SIMBAD's main features include a database of identifications, aliases, and names of astronomical objects, a complete and up-to-date bibliographic survey, and a Dictionary of Nomenclature for managing complex object nomenclature. The database management system is developed in-house using object-oriented programming concepts. SIMBAD is kept up-to-date daily through collaboration with bibliographers. The database includes data on object types, coordinates, proper motion, parallax, radial velocity or redshift, magnitudes, spectral types, and morphological types of galaxies. It also includes cross-identifications, observational data, and bibliographical references. The database is accessible through various interfaces, including a WWW interface, command line interface, and client/server mode. SIMBAD is a charged service with user accounts managed by CDS. It is used by astronomers worldwide for research and data retrieval. The database is updated daily through collaboration with bibliographers and includes data from various sources. The database is maintained by CDS and is available through a mirror at Harvard. The database is updated weekly and includes new acronyms. The Dictionary of Nomenclature is maintained by CDS and provides information on astronomical object designations.SIMBAD is the reference database for identification and bibliography of astronomical objects. It contains identifications, 'basic data', bibliography, and selected observational measurements for several million astronomical objects. Developed and maintained by CDS, Strasbourg, SIMBAD is built with contributions from various institutes. It includes catalogues and tables selected for optimal multi-wavelength coverage and research support. The database is updated daily through collaboration with bibliographers. A WWW interface is available at http://simbad.u-strasbg.fr/Simbad. SIMBAD contains information for over 2.7 million astronomical objects, including stars, galaxies, and non-stellar objects. It includes cross-identifications from 4500 catalogues and tables, observational data from 25 types of data catalogues, and a bibliographic survey covering astronomical literature since 1950 for stars and since 1983 for extragalactic objects. The database is organized per astronomical object, providing users with all published information about any given object. SIMBAD's main features include a database of identifications, aliases, and names of astronomical objects, a complete and up-to-date bibliographic survey, and a Dictionary of Nomenclature for managing complex object nomenclature. The database management system is developed in-house using object-oriented programming concepts. SIMBAD is kept up-to-date daily through collaboration with bibliographers. The database includes data on object types, coordinates, proper motion, parallax, radial velocity or redshift, magnitudes, spectral types, and morphological types of galaxies. It also includes cross-identifications, observational data, and bibliographical references. The database is accessible through various interfaces, including a WWW interface, command line interface, and client/server mode. SIMBAD is a charged service with user accounts managed by CDS. It is used by astronomers worldwide for research and data retrieval. The database is updated daily through collaboration with bibliographers and includes data from various sources. The database is maintained by CDS and is available through a mirror at Harvard. The database is updated weekly and includes new acronyms. The Dictionary of Nomenclature is maintained by CDS and provides information on astronomical object designations.