Open outcry

It involves shouting and the use of hand signals to transfer information primarily about buy and sell orders.

Since the development of the stock exchange in the 17th century in Amsterdam, open outcry was the main method used to communicate among traders.

The supporters of electronic trading claim that it is faster, cheaper, more efficient for users, and less prone to manipulation by market makers and broker/dealers.

As of 2010, most stocks and futures contracts were no longer traded using open outcry due to the lower cost of the aforementioned technological advances.

As of 2017, open outcry in the United States was very limited, such as in a much more stream-lined form at the Chicago Board of Trade owned by the CME Group.

That means that the traders actually form a group around the post on the floor of the market for the specialist, someone that works for one of the NYSE member firms and handles the stock.

[3] Floor hand signals are used to communicate buy and sell information in an open outcry trading environment.

The signals can otherwise be used to indicate months, specific trade or option combinations, or additional market information.

Until 2009, [ 1 ] trades on the floor of the New York Stock Exchange always involved a face-to-face interaction . There is one podium/desk on the trading floor for each of the exchange's three thousand or so stocks.
The New York stock exchange trading floor in September 1963, before the introduction of electronic readouts and computer screens
Open outcry "pit" at the Chicago Board of Trade (CBOT) in 1993
CBOT "The Pit" in 1908
Hand signalling on the floor of the Chinese Gold and Silver Exchange Society