Abstract:  In this talk, I will explore two recent developments in the search for dark matter. First, I will discuss how the 21-cm global signal measurement constrains the potential impact of dark matter annihilation/decay on the thermal history of the universe. I will also explain how to accurately compute such modifications to the baryon temperature in the early universe using a soon-to-be-released public code called DarkHistory. Second, I will discuss the Axion Detection with Birefringent Cavities (ADBC) experiment, which aims to observe rotations induced by axion dark matter in the polarization of light using optical interferometry techniques.