The document discusses the nature and phases of trade cycles. Trade cycles refer to fluctuations in economic activity over months or years. There are four phases - expansion/boom, recession, depression/contraction, and recovery/revival. The expansion phase sees high investment, output, employment and prices. The recession phase brings falling income, output, prices and rising unemployment. Depression is characterized by mass unemployment, low output and prices. Recovery occurs when investment and output begin rising again. Governments use monetary and fiscal policy to reduce the impact of trade cycle fluctuations.