The first living cell was observed by Antonie van Leeuwenhoek in the 1670s, with his documented observations of living pond microorganisms and other microscopic life marks a key milestone in microbiology. His work in the 1670s using handcrafted single-lens microscopes revealed living cells such as protozoa and bacteria, establishing the reality of microorganisms as living entities and earning him the title often given as the "Father of Microbiology."