The document discusses primary health centers (PHCs) in India. PHCs are the most basic and important unit of public healthcare, aiming to provide accessible and affordable primary care. They typically cover populations of 20,000-30,000 people. PHCs serve as the first point of contact for village communities, offering curative, preventive and promotive health services. Their focus is on programs for infant immunization, controlling epidemics, birth control, pregnancy care and more.