NYSE (New York Stock Exchange), nicknamed the "Big Board", is the largest stock exchange in the U.S., located on Wall Street in New York City. The NYSE is responsible for setting policy, supervising member activities, listing securities, overseeing the transfer of member seats, and evaluating applicants.

Unlike some of the newer exchanges, the NYSE still uses a large trading floor in order to conduct its transactions. It is here that the representatives of buyers and sellers, professionals known as brokers, meet and shout out prices at one another in order to strike a deal.

Most academic literature shows NYSE stocks trade better (in tighter ranges, less volatility, less difference in price between trades) when compared with the OTC market (NASDAQ). On the NYSE 93% of trades occur at no change or 1/8 of a point difference. It is counterintuitive that one spec could make a better market than many market makers. However, the spec operates under an entirely different system. The NYSE system requires exposure of public orders to the auction, the opportunity for price improvement, and to trade ahead of the dealer. The system on the NYSE is very different than NASDAQ and has been shown to create a better market for the stocks listed there. This is why 90% of US stocks that are eligible for NYSE listing have listed.

Every listed stock has one firm assigned to it on the floor. Most stocks are also listed on regional exchanges in LA, SF, Chi., Phil., and Bos. All NYSE trading (approx 80% of total volume) will occur at that post on the floor of the specialist assigned to it.

NYSE Group merged with Euronext, and many of its operations (particularly IT and the trading platform) will be combined with that of the New York Stock Exchange and NYSE Arca.