Digital stock tickers crawling across the bottom of the TV screens and computer monitors are based on 19th-century telegraph-era technology, but today offer real-time updates on market movements. Traders and investors use the information broadcast on tickers to help gauge intraday market sentiment.
The first tickers were long strips of paper ("ticker tapes") with first morse code and later letters and numbers printed on, indicating the market movements ("ticks" on the printer) of stocks on an exchange. Along the tape, a string of three, four or five letters indicate the security name and exchange it trades on - some are intuitive (brewer Anheuser Busch trades as BUD) but many aren't so most observers use lists. Numbers after the letters indicate latest price, shares traded and price change up or down. Television stations like CNBC show ticker tapes of different colors - green for stock trading up, white or blue for price unchanged and red for stock trading down. Today many trading and investment websites offer free, customizable stock tickers that can be adjusted to track a number of individual securities and portfolios.