Price Mechanism - Stock Market

Stock Market

When trading in a stock market, a person who has shares to sell may not wish to sell them at the current market price (quote). Likewise, a person who wishes to buy shares may not wish to pay the current market price either. Some negotiation is necessary in order for a transaction to occur.

The negotiation often comes in the form of adjusting the bid prices and the ask prices as the value of the share goes up and down. For example, if the share is worth $10, a buyer may "bid" $9.97 (3 cents less), and a seller may ask for $10.02 (2 cents more). If the value of the stock goes down, a seller may be forced to reduce his asking price. Conversely, if the value of the stock goes up, a buyer may be forced to increase his bidding price.

Most of the time, the bid and ask prices remain very close to the market value of the share, often separated by only a couple of cents. The difference between the bid and ask price is called the Bid/ask spread.

In actual trading, the parties involved might use a limit order to specify which bid or ask price he wishes to trade at. The trader specifies the number of shares and his bid/ask price (depending on whether he is buying or selling). Such orders can have execution limits, such as "by end of day" or "all or nothing".