Explore black hole astrophysics through gravitational-wave catalogs in this 45-minute conference talk by Maya Fishbach from Northwestern University. Delve into the properties of binary black hole populations, including mass distribution, spin distribution, and redshift evolution. Discover astrophysical insights about black hole formation, focusing on the pair-instability mass gap and time delays between formation and merger. Examine LIGO and Virgo observations of over 40 black hole mergers, including neutron star-black hole systems. Learn about parameter estimation, effective inspiral spin population distribution, and merger rate evolution compared to star formation time delays. Investigate outlier tests with coarse-grained likelihoods and semiparametric population fits in GWTC-3. Gain understanding of population-level correlations and discuss remaining mysteries about black hole origins, as well as expectations for future observations in gravitational wave astronomy.