the stock market since its inception gets a great development, particularly in the Western States and Eastern Asia, as it moved with giant strides on the level of products and financial structures, legislation and regulations and other aspects of evolution and improvement,
The stock started its activities with limited products and structures (in cafes or at home) and without any means approximately, and reaching the status of progress in techniques and tools, helped in that the technological development occurred in the means of communication of information, so its Activities expanded.
example of this evolution reached by both Tokyo and New York stock exchanges (Wall Street) these two stock exchange are in the beginning of all other global bourses with a vast difference although they are newly independent Covenant compared to European stock exchanges (such as the Brussels Stock Exchange which is considered the oldest stock exchanges but had little significance) both in terms of capitalization or friendly value securities, the stock market has played an active role in the development of the economies of major countries.
The most effective of these roles or objectives are:
-collect savings to finance national economy.
- Dissemination of social capital of enterprises and the public in the form of bonds and equities.
- measuring and knowing the status of the national economy and that through the knowledge of the effectiveness of the financial markets, which in turn lead to effectiveness and efficiency of the economy.
In addition, the stock market could be affected by several factors, including:
• political events, in particular, lead to higher prices for traded values or vice versa.
• discover gold mines, oil, inventions, interest rates, price level....
In addition to other objectives, reflected in the ease and speed of trading values in circulation.
Despite this considerable importance, we noted that the stock market as a foundation for work in the vicinity is characterized by conditions of uncertainty and exposed to violent shocks lead to the bankruptcy of many.
In a world characterized by rapid change in terms of stock exchanges caused economic disaster in a form of multiple collapses of varying duration and the degree and led to a significant decline in stock prices and traded on the stock exchanges.
Three avalanches that hit the stock exchange:
The collapse of 1929: bringing the 5000 us Bank into bankruptcy, and prosecutors have lost three million dollars, and the recession prevailed all over the world.
*the collapse of 1987: stock and stock price declines in global stock exchanges (lower price and price components indicators such as the Dow Jones industrial ) but it less in degree of the collapse in 1929
*The collapse of 1989: is a small collapse (a loss of 200 billion us dollars) in addition to the small new stalls.
keeps referring to every collapse has its own theoretical causes as each specialize attempts to specify what must be said is that these collapses are all lead to losses which are reflected at the level of global economies.