James Watson and Francis Crick, working at Cambridge University, announced they had discovered the double-helix structure of DNA. Their model was heavily based on X-ray diffraction images taken by Rosalind Franklin and Maurice Wilkins. This discovery revealed how genetic information is stored and replicated in living organisms. It is considered the most important biological discovery of the 20th century, paving the way for the fields of genetics, biotechnology, and the Human Genome Project. It allowed scientists to begin understanding the 'instruction manual' for life, leading to modern breakthroughs in forensic science, agriculture, and the treatment of genetic diseases.