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The Fermi Gamma-ray Burst Monitor (GBM) has been observing Terrestrial Gamma-ray Flashes (TGFs) along with other astrophysical phenomena for over a decade. The low-earth orbit of Fermi combined with improved offline TGF search techniques results in unprecedentedly large TGF dataset comprised of more than 4000 such events [Roberts et al., JGR, 123, 4381, 2018]. The two dimensional source location of a TGF, observed by the GBM is obtained by correlating the time of occurrence of the TGF with that of the associated radio frequency (RF) emission reported by a lightning locating system (LLS). The precise geolocation of TGFs is necessary for generating detectors’ response matrices allowing to study the TGF production mechanisms using various models. However, due to high photon rates and low number of counts, studying individual TGFs can be challenging. The GBM onboard Fermi spacecraft has observed tens of sufficiently bright events, which are suitable for the individual analysis. Mailyan et al., [JGR, 121, 11346, 2016] for the first time fit individual, bright TGFs with Relativistic Runaway Electron Avalanche (RREA) models [Dwyer, GRL, 30, 2055, 2003]. RREA models assume that the TGF-producing electron acceleration takes place in a large-scale homogeneous field, presumably seeded by secondary cosmic rays. Alternatively, lightning leader models consider the acceleration in an inhomogeneous field of lightning [Celestin et al., JGR, 120, 10712, 2015]. The predictions of the latter models for the TGF beaming geometry show some differences from estimations of the RREA models in homogeneous fields. Moreover, the RF emissions from TGFs themselves can give insights into TGF production and characteristics of the storms, which produce those gamma-ray flashes. In this work, we present an overview of recent advances in TGF research as well as some other phenomena observed by with Fermi-GBM.