Although public health has historically been defined by core functions such as the control of infectious diseases, sanitation, and vaccination, it carries a much broader and more dynamic meaning today. In this section, the major developments and conceptual transformations that have reshaped the contemporary understanding of public health are comprehensively addressed. The burden of disease is closely linked not only to individual behaviors but also to social conditions such as income, education, housing, and environmental exposures.

In the field of digital public health, innovations such as artificial intelligence, big data analysis, and telehealth offer significant advantages in monitoring public health and guiding health policies. However, while discussing the benefits of these technologies, we must not overlook the risk of not everyone having equal access to technology (digital inequality).

The ‘One Health’ approach shows us this: human, animal, and environmental health form a whole and cannot be considered separately from one another. Addressing these three areas together and holistically is no longer a choice but a necessity, particularly in order to cope with global threats such as antibiotic resistance and zoonotic diseases transmitted from animals to humans.

In this section, where we examine in detail the multifaceted impacts of climate change on human health and the value of structural, community-based interventions in preventing chronic diseases, we will also explore critical contemporary issues such as health literacy, information pollution (infodemic) management, community mental health, and psychosocial resilience under separate headings.

The resilience of health systems in disaster and pandemic preparedness, the well-being of healthcare workers and workforce sustainability, and healthy aging are also among the chapter’s primary focal points.

Throughout the section, the intersecting functions of primary healthcare services with public health are emphasized, and at the point we have reached, one conclusion is very clear: The role of public health is not merely to prevent diseases, but to also build the very conditions that will enable a healthy life.