Results. Multiwavelength correlations suggest that radio-loud sources host relativistic jets that are the predominant sources of radio, optical, and X-ray emission. The origin of infrared emission remains unclear. Radio-quiet sources do not host a jet, or the jet is very weak. In them, radio and infrared emission is more likely generated via star formation processes, and the optical and X-ray emission originate in the inner parts of the AGN. We also find that the black hole mass correlates significantly with radio loudness, which suggests that NLS1 galaxies with more massive black holes are more likely to be able to launch powerful relativistic jets.