India is undertaking the biggest population count the world has ever attempted - a digital census designed to capture the lives, identities and realities of more than 1.4 billion people. With three million field staff, self‑enumeration in 16 languages, and real‑time monitoring across cities, forests, floodplains and megacities, the operation is both a national ritual and a vast technological experiment. The census reaches far beyond population totals. It records religion, language, housing, migration, education, work, and for the first time in nearly a century, caste.