Over the Counter

The least prestigious and most obscure market to the public is also without a doubt the single largest. The vast majority of stocks don't trade in the previously described physical markets at all. Rather, they trade on a highly sophisticated computer network called the National Market System (NMS). The NMS is absolutely massive in scope, listing and trading trillions of shares of thousands upon thousands of different stocks.

The number of trades and stock listed on the over the counter (OTC) market dwarfs any physical exchange anywhere. However, as OTC is a computerized network rather than a physical marketplace, it does not maintain the glamour of old buildings and yelling traders. For that reason, many people will erroneously omit the OTC when discussing markets.