Deflation....what does deflation means?

                                             
In economics, deflation is a decrease in the general price level of goods and services.^[1] Deflation occurs when the inflation rate falls below 0% (a negative inflation rate). This should not be confused with disinflation, a slow-down in the inflation rate (i.e., when inflation declines to lower levels).^[2] Inflation reduces the real value of money over time; conversely, deflation increases the real value of money – the currency of a national or regional economy. This allows one to buy more goods with the same amount of money over time.

Economists generally believe that deflation is a problem in a modern economy because it increases the real value of debt, and may aggravate recessions and lead to a deflationary spiral.^[3] Historically not all episodes of deflation correspond with periods of poor economic growth.^[4] Deflation occurred in the U.S. during most of the 19th century (the most important exception was during the Civil War). This deflation was caused by technological progress that created significant economic growth.^[5][6][7] This deflationary period of considerable economic progress preceded the establishment of the U.S. Federal Reserve System and its active management of monetary matters.

deflation is caused by a shift in the supply and demand curve for goods and services, particularly a fall in the aggregate level of demand. That is, there is a fall in how much the whole economy is willing to buy, and the going price for goods. Because the price of goods is falling, consumers have an incentive to delay purchases and consumption until prices fall further, which in turn reduces overall economic activity. Since this idles the productive capacity, investment also falls, leading to further reductions in aggregate demand. This is the deflationary spiral. An answer to falling aggregate demand is stimulus, either from the central bank, by expanding the money supply, or by the fiscal authority to increase demand, and to borrow at interest rates which are below those available to private entities.