AUTHOR=Gamble Ronald , Forman Jordan , Barnes Amethyst , Srinivasaragavan Gokul , Holt Isiah , Jones Marvin TITLE=Multi-messenger emission characteristics of blazars JOURNAL=Frontiers in Astronomy and Space Sciences VOLUME=Volume 11 - 2024 YEAR=2024 URL=https://www.frontiersin.org/journals/astronomy-and-space-sciences/articles/10.3389/fspas.2024.1401891 DOI=10.3389/fspas.2024.1401891 ISSN=2296-987X ABSTRACT=Multi-messenger observations and theories of astrophysical objects are rapidly becoming a critical research area in the astrophysics scientific community. In particular, point-like objects such as BL Lacertae (BL Lac) objects, flat-spectrum radio quasars (FSRQs), and blazar candidates of uncertain type (BCUs) are of distinct interest to researchers studying the synchrotron, Compton, neutrino, and cosmic ray emissions sourced from compact objects. Notably, there is also much interest in the correlation between multi-frequency observations of blazars and neutrino surveys on source demographics. In this review, we look at such multi-frequency and multi-physics correlations of the radio, X-ray, and γ-ray fluxes of different classes of blazars from a collection of survey catalogs. This multi-physics survey of blazars shows that there are characteristic cross-correlations in the spectra of blazars when considering their multi-frequency and multi-messenger emission. In addition, a review of cosmic ray and neutrino emissions from blazars and their characteristics is presented.