Demography (from prefix demo- from Ancient Greek δῆμος dēmos meaning "the people", and -graphy from γράφω graphō, ies "writing, description or measurement") is the statistical study of populations, especially human beings.
Demographic analysis can cover whole societies or groups defined by criteria such as education, nationality, religion, and ethnicity. Educational institutions usually treat demography as a field of sociology, though there are a number of independent demography departments. Based on the demographic research of the earth, earth's population up to the year 2050 and 2100 can be estimated by demographers.
Patient demographics form the core of the data for any medical institution,such as patient and emergency contact information and patient medical record data. They allow for the identification of a patient and his categorization into categories for the purpose of statistical analysis. Patient demographics include: Date of birth, gender(Ref: Google Health),Date of death, postal code, ethnicity, blood type (Ref: Microsoft HealthVault: Personal Demographic Information, Basic Demographic Information),Emergency contact information, family doctor, insurance provider data, Allergies, major diagnoses and major medical history.Formal demography limits its object of study to the measurement of population processes, while the broader field of social demography or population studies also analyses the relationships between economic, social, cultural, and biological processes influencing a population.