DNA’s double-helix structure was determined in 1953 by James Watson and Francis Crick, with critical data from Maurice Wilkins and Rosalind Franklin contributing to the breakthrough. Franklin’s X-ray diffraction work, including the famous Photo 51, provided essential evidence that helped shape the correct model, though she did not share the Nobel Prize awarded later to Watson, Crick, and Wilkins. Early groundwork on DNA’s chemistry and components was laid by Friedrich Miescher in the 1860s and later expanded by scientists such as Phoebus Levene and Erwin Chargaff, who elucidated base composition and pairing rules that underpinned the Watson–Crick model. The discovery is thus best viewed as a collaborative, multi-decade effort spanning several researchers who built on one another’s findings.