The activities that man carried over along his history have been characterized by developing of an own language that differentiate them from other tasks. Since Bretton Woods treaty was finished and the free flotation of the dollar was set out, regulated only by supply and demand, investment in foreign currency has become a very popular activity and have had reached sectors which years ago look on the purchase and sale of money unfavourably. The inversion in currencies has it’s own language and that is necessary to understand in order to maintain a smooth communication with the operators. Here we will develop some concepts for you to get familiarized with the market vocabulary. Agent: someone who acts as principal or counterpart of a currencies investment or transaction, place the buy and sell order. Mark to Market (End of Day): The operators represent their positions by two ways: accrual or adjustment to the market. A system that is based on the accrued represents only the cash flow, when they occur, therefore, they only show a profit or a loss. The Mark to Market method assesses the operator registry at the end of each working day using the closing market rates or re valuating rates . All gains or losses that occur in currencies investing are recorded. Fundamental analysis: In currencies investment this analysis is based on the observation of the economic and political data in order to determine future movements in the financial market. Increasing exchange rate: When you invest in foreign exchange it’s said that a currency is increasing it’s exchange rate when the price increases in response to market demand, an increase in an asset value.