OTD:

In 1683, Antonie van Leeuwenhoek described his discovery of single-celled organisms, revolutionizing microbiology with his observations of bacteria.

In 1787, the U.S. Constitution was signed in Philadelphia, establishing the framework for a democratic republic with a system of checks and balances.

In 1890, Sir William Halford patented an improved electric arc lighting system, enhancing safety and efficiency in public and industrial lighting.

In 1908, Gustav Mahler’s Symphony No. 7 premiered in Vienna, showcasing his innovative blend of musical styles and textures.

In 1923, the Great Kanto Earthquake struck Japan, causing widespread devastation, fires, and the deaths of over 140,000 people.

In 1939, the Soviet Union invaded Poland as part of a secret pact with Nazi Germany, contributing to Poland's occupation and suffering.

In 1972, Mark Spitz set a world record by winning his seventh gold medal at the Munich Olympics, a record that stood for 36 years.

In 1983, the first AI conference, IJCAI, was held in Toronto, shaping future AI research and fostering international collaboration in the field.

In 2000, the NASDAQ Composite peaked during the dot-com bubble before its collapse, marking the beginning of an economic downturn.

In 2008, Satoshi Nakamoto introduced Bitcoin, laying the foundation for the first decentralized digital currency through a cryptography mailing list.