Edward Callahan’s stock ticker enables market prices to be transmitted rapidly, improving access to trading information.

On 15 November 1867, the stock ticker was introduced at the New York Stock Exchange (NYSE), marking a major advancement in financial communication and stock market technology. Invented by Edward A. Calahan, the stock ticker used telegraph technology to transmit stock prices rapidly to brokers and investors. The machine printed abbreviated company names and their latest trading prices on narrow strips of paper known as ticker tape. This innovation significantly improved the speed and accuracy of financial information, allowing market participants to follow stock price movements more efficiently. The introduction of the stock ticker transformed the American financial industry by making market information more accessible and reducing delays in communicating trading prices. Before its invention, brokers relied heavily on messengers and handwritten updates to obtain stock quotations. Calahan's technology helped modernize trading practices, improve market transparency, and support the continued expansion of the NYSE. The stock ticker became an iconic symbol of Wall Street and laid the foundation for modern electronic market data systems and real-time financial reporting.