The fundamental and simple rule of profitable trading at financial markets is to buy cheaper and sell dearer. Thus, the entire trading activities at financial markets come to the successive operations performed to sell or buy securities. To do so, one has to open, modify, and close trade positions. Trade position is a market commitment (order), the number of bought or sold contracts for which no set-off transactions have been made. The entire trading in the terminal is implemented through trade positions.
To open a trade position, one has to make a transaction, and to close a position, one has to make an inverse operation. A position can be opened by a brokerage company at a market order or at execution of a pending order. An open position can be modified if values of the Stop Loss and Take Profit orders levels attached to the position are changed. Positions can be closed on the trader's demand or at execution of Stop Loss or Take Profit orders. Besides, positions can be opened, modified, or closed with an expert advisor — this mechanism is described in another section.