Walgreens is one of the largest pharmacy chains in the United States, providing prescription medications, over-the-counter drugs, health and wellness products, and pharmacy services. Founded in 1901 in Chicago, Illinois, the company operates thousands of retail locations across the country and is part of Walgreens Boots Alliance. Walgreens plays a significant role in U.S. healthcare delivery, offering immunizations, health screenings, and other clinical services alongside its retail operations.