Ticker tape

Ticker tape was the earliest electrical dedicated financial communications medium, transmitting stock price information over telegraph lines, in use from around 1870 through 1970. It consisted of a paper strip that ran through a machine called a stock ticker, which printed abbreviated company names as alphabetic symbols followed by numeric stock transaction price and volume information. The term "ticker" came from the sound made by the machine as it printed. The ticker tape revolutionized financial markets, as it relayed information from trading floors continuously and simultaneously across geographical distances. Paper ticker tape became obsolete in the 1960s, as television and computers were increasingly used to transmit financial information. The concept of the stock ticker lives on, however, in the scrolling electronic tickers seen on brokerage walls and on news and financial television channels. Ticker tape stock price telegraphs were invented in 1867 by Edward A. Calahan, an employee of the American Telegraph Company who later founded The ADT Corporation. Although telegraphic printing systems were first invented by Royal Earl House in 1846, early models were fragile, required hand-cranked power, frequently went out of synchronization between sender and receiver, and did not become popular in widespread commercial use. David E. Hughes improved the printing telegraph design with clockwork weight power in 1856, and his design was further improved and became viable for commercial use when George M. Phelps devised a resynchronization system in 1858. The first stock price ticker system using a telegraphic printer was invented by Edward A. Calahan in 1863; he unveiled his device in New York City on November 15, 1867. Early versions of stock tickers provided the first mechanical means of conveying stock prices ("quotes"), over a long distance via telegraph wiring. In its infancy, the ticker used the same symbols as Morse code as a medium for conveying messages.