The decision to hold this IAU Symposium at Bologna on the occasion of the 100th anniversary of the discovery of the wireless telegraphy represents in itself a recognition of the widespread feeling of a historical link between the great discovery of Guglielmo Marconi and the birth of radioastronomy. Obviously, it is not a direct link. We all well know that the birth of radioastronomy must be traced back to the year 1932 when Karl Jansky recognized for the first time the existence of a radio signal probably associated with a celestial source. This a classical example of a ‘serendipitous’ discovery made while Jansky was investigating for the Bell Telephone Laboratories the sources of radio interferences with a rotating antenna array operating at about 14 m wavelength. The study of local disturbances was of primary importance in the rapid development of radio communications which had been geared by the Marconi's discovery.