**6. Summary and Discussion**

It is almost five decades after the first GRB was discovered in the 1960s, and since then, there are observations of ∼ 1000 GRBs at different redshifts. These observations have made progress over the years in detecting GRB luminosity and the light curve of the afterglow more accurately, and in advanced spectra aiming to decisively determine the nature of the GRB progenitor and progenitor-circumstellar medium (CSM) interaction. This progenitor-CSM interaction provides hints to the ISM compositions of the host galaxies, and thereby has enriched our understanding of the high-redshift universe. Moreover, the precision to pinpoint the GRB location has also enhanced our knowledge of the host galaxies. A strong correlation between LGRB and Type-Ic SN has broadened our understanding of LGRB progenitors as well.

Even though all these advances have made a clearer picture of GRB production, there are still several open questions yet to be answered:


**Funding:** This research received no external funding.

**Data Availability Statement:** Data underlying this article will be shared on reasonable request to the author.

**Acknowledgments:** We thank anonymous referees for their insightful comments to enrich the manuscript. AR is grateful to Mark Krumholz and Alexander Heger for their valuable inputs and suggestions. AR gratefully acknowledges the support from Andrea Ferrara's Italian funding scheme "The quest for the first stars" (Cod. 2017T4ARJ5\_001). AR also gratefully acknowledges support from Mark Krumholz's Australian Research Council's *Discovery Projects* and *Future Fellowship* funding scheme, awards DP190101258 and FT180100375. Parts of this research were conducted by the Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. This research/project was undertaken with the assistance of resources and services from the National Computational Infrastructure (NCI)'s supercomputer Gadi, which is supported by the Australian Government, and the Australian National University's Research School of Astronomy & Astrophysics's cluster Avatar.

**Conflicts of Interest:** The author declares no conflict of interest.
