Although it is a crucial pat of our cosmic timeline, Cosmic Dawn—when the first stars and galaxies formed and systematically reionized the intergalactic medium—remains relatively unexplored. By tracing the distribution and state of neutral hydrogen, 21cm cosmology promises to provide the first direct observations of Cosmic Dawn. The Hydrogen Epoch of Reionization Array (HERA) is a low-frequency radio interferometer that is poised to realize this promise within the next few years by making large-scale observations of the 6 < z < 20 universe. In this talk, I will provide an overview of the scientific capabilities of HERA as well as a status update on high-z 21cm cosmology. Along the way, I will also describe our recent efforts in modeling foreground contaminants in the data, how machine learning can be used in our data analyses, and how 21cm cosmology may complement Cosmic Microwave Background observations with better constraints on reionization.