Life expectancy is a statistical measure indicating the average number of years a person can be expected to live from a particular age, such as birth, based on current mortality rates and demographic conditions within a specific population. It is a key indicator of a population's overall health and well-being, reflecting factors such as access to healthcare, nutrition, sanitation, environmental quality, and lifestyle choices. Life expectancy can vary significantly across different countries, regions, and social groups due to disparities in these underlying factors. Improvements in public health, medical advancements, and socioeconomic development have led to significant increases in life expectancy in many parts of the world over the past century. Demographers and sociologists study life expectancy to understand population trends, health disparities, and the social and environmental determinants of longevity.