Take a moment to look at the massive, neoclassical building at eighteen Broad Street with its iconic Corinthian columns. This is the New York Stock Exchange, completed in 1903 by architect George B. Post. Its marble facade was designed to look like a temple, signaling strength and stability to the world. However, American finance began much more modestly. In 1792, 24 stockbrokers signed the famous Buttonwood Agreement, allegedly under a buttonwood tree that once grew near 68 Wall Street. This simple document established the first rules for trading securities and set a fixed commission rate, effectively birthing the modern stock market. The brokers would often meet in nearby coffee houses, like the Tontine Coffee House, because they had no formal exchange building yet. Today, you can still see a symbolic buttonwood tree planted right outside the Stock Exchange's main entrance. It is a living reminder that the trillions of dollars flowing through these digital networks today all started with a simple handshake beneath a tree.