Market Maker - A firm which can afford the jeopardy of holding numerous shares of a particular security, in order to facilitate trading that security in.
The market maker gives his clients buy and sells quotations for a guaranteed number of shares he can instantaneously sell from its own stock.
Dealer Market - A market which dealers are assigned for a definite securities and creating liquid markets by buying and selling against individuals accounts.
Liquid Market - created when there is a market with many bid and ask offers.
Limit Order - An order a trader give his broker/ firm to buy or sell number of shares at a particular price.
Leverage - The use of a borrowed capital, such as Margin, in afford to enlarge the potential return of an asset.
Margin Call - Aka maintenance call, when a broker demands from a client who use margin to deposit additional money.
Weak Longs - refers to investors that hold a long position and sell that position at the first sign of weakness or at round numbers.
Long/Short Equity - A FOREX strategy used by hedge funds that based on buying certain stocks long and selling others short.
Stop Hunting - A FOREX strategy which tries to force some investors out of their positions by driving the price of a currency pair to a level where many investors have chosen to set their stop-loss orders.
Trend Trading - a FOREX strategy which tries to gain profit thought the analysis of an asset's momentum in a particular direction, i.e. entering a long position when a stock is trending upward.
