The exponential increase in internet use and the consequent surge in data generation present both opportunities and challenges for public health. Infodemiology, an emerging field at the intersection of information science and public health, seeks to harness the vast amounts of health-related data generated online for public health benefits. This paper provides a comprehensive overview of infodemiology, examining its development, methodologies, and potential to address public health challenges. We discuss the role of infodemiology in identifying and mitigating the spread of misinformation, especially in the context of the COVID-19 pandemic, which underscored the dangers of the "infodemic" – an overabundance of information, both accurate and not, that complicates public health responses. Through both demand and supply-based studies, infodemiology offers unique insights into health trends, misinformation dynamics, and the digital behaviors of health information seekers. Tools such as sentiment analysis are highlighted as essential in navigating the vast digital landscape for real-time health data analysis. Despite the potential of infodemiology, challenges such as data overload or misinformation. The paper concludes by emphasizing the importance of interdisciplinary collaboration, the development of advanced analytical tools, and the need for guidelines to maximize the field's impact on public health policy and practice.