This document provides an overview of the Affordable Care Act (ACA) including key provisions, implementation challenges, and political aspects. It discusses major reforms such as prohibiting denial of coverage for pre-existing conditions, essential health benefits, subsidies for low-income individuals, health insurance exchanges, and penalties for large employers not providing coverage. Implementation has resulted in over 16 million more Americans with health insurance but ongoing issues include rising costs, inadequate provider networks, and legal challenges to the ACA.