Pfizer Inc. is a global biopharmaceutical company headquartered in New York City, renowned for its research-based approach to developing and manufacturing medicines and vaccines. Established in 1849, Pfizer has become one of the world's largest pharmaceutical firms, employing approximately 81,000 people worldwide. Its diverse portfolio spans therapeutic areas such as oncology, immunology, cardiology, and infectious diseases, with notable products including the COVID-19 vaccine Comirnaty, the cholesterol medication Lipitor, and the erectile dysfunction drug Viagra. The company is also investing in mRNA technology and global health initiatives to expand access to essential medicines and vaccines.