Preventive medicine or preventive care refers to measures taken to prevent diseases, (or injuries) rather than curing them or treating their symptoms. The term contrasts in method with curative and palliative medicine, and in scope with public health methods (which work at the level of population health rather than individual health).

Preventive medicine strategies are typically described as taking place at the primary, secondary, tertiary and quaternary prevention levels. In addition, the term primal prevention has been used to describe all measures taken to ensure fetal well-being and prevent any long-term health consequences from gestational history and/or disease. The rationale for such efforts is the evidence demonstrating the link between fetal well-being, or "primal health," and adult health.; Primal prevention strategies typically focus on providing future parents with: education regarding the consequences of epigenetic influences on their child, sufficient leave time for both parents, and financial support if required. This includes parenting in infancy as well.

Johns Hopkins (May 19, 1795 – December 24, 1873) was an American entrepreneur, abolitionist and philanthropist of 19th-century Baltimore, Maryland.

His bequests founded numerous institutions bearing his name, including Johns Hopkins Hospital, Johns Hopkins University, Johns Hopkins School of Nursing, Johns Hopkins School of Medicine, and Johns Hopkins Bloomberg School of Public Health.

A biography entitled Johns Hopkins: A Silhouette written by his cousin, Helen Hopkins Thom, was published in 1929 by the Johns Hopkins University Press.

Johns Hopkins was born on May 19, 1795, to Samuel Hopkins (1759–1814) of Anne Arundel County, Maryland, and Hannah Janney (1774–1864), of Loudoun County, Virginia. Home was Whitehall, a 500-acre (two km²) tobacco plantation in Anne Arundel County. His first name derives from a maternal great-grandmother, Margaret Johns, who passed it on to her son.

The Hopkins family were members of the Society of Friends (Quakers). In 1807 they emancipated their slaves in accordance with their local Society decree, which called for freeing the able-bodied and caring for the others, who would remain at the plantation and provide labor as they could. The second eldest of eleven children, 12 year-old Johns was required to work on the farm, interrupting his formal education. From 1806 to 1809, he likely attended The Free School of Anne Arundel County, which was located in today's Davidsonville, Maryland.