Today’s historic plummet of stock prices in New York may have been triggered by what is going on with the credit crisis in Greece and the rest of Europe; it may also have been aided by the Chinese "readjustment" of its money to account for inflation; but the most probable rumor is that high-speed, computerized algorithmic trading used by institutional investors is what caused stock prices to plunge 700 points in a 10-minute span. Again, the technology works, but the training and accountability of people and processes that are engaged in the technology are the true point of concern. The purge in the stock market today exemplified the importance of addressing the "human factor" in handling technology. Until the focus on people and processes is addressed in a serious manner (not fluffed by more regulation that is not likely to be enforced), this may be the "norm" for the future of trading stocks. Makes one really reconsider whether investing in the markets is a smart thing to do with ones hard-earned money.
Read the following article, and keep this point in mind: U.S. Stock Plunge Raises Alarm on Algo Trading