There are many different jobs on the floor of the stock market. Each market depends on different types of people doing different types of job to keep the market in order. .
In an article recently published by the Wall Street Journal called, "Who are these Specialists under Fire from the NYSE?" These specialists are under fire because they are using inside knowledge to gain in advantage for their firms. Basically they are more concerned with the firm making the profit then the customer.
A specialist job has changed quite a bit however due to technology. Until recently specialist used to get all their information from brokers on the floor. Now they use a big board that is electronic and has all the information stored on the computer, compared to printed cards which was much less organized.
With the New York Stock Exchange there are people who are called specialist. Specialists make up the second largest amount of people on the floor behind commission brokers. A specialist main job is to act as a dealer in a small number of securities on the exchange floor. They are supposed to maintain a fair and orderly manner when regulating the securities assigned to them.
Specialist post bid prices and ask prices for securities assigned for them. Specialist buy at bid prices and sell at ask prices and when there is a disparity between buyers bid price and sellers ask price. That is how they make their money.