投资人买卖股票，在于从股票价格波动中，博取差价，获得收益。股票的价格时时变动，影响价格变动的因素来自多方面，既有来自市场内部的技术因素，诸如人为操纵、交易者成份、交易量等等；又有来自市场外部的基本因素，即政治因素和经济因素，如国家政策、经济形势、企业经营 Investors buy and sell stocks, lies in the stock price fluctuations, access to the spread, gain. The price of stock fluctuates from time to time, and the factors that affect the price change come from many aspects, including the technical factors from inside the market, such as human manipulation, trader’s composition, trading volume and so on; and the basic factors from the outside of the market, namely, political factors and Economic factors, such as national policies, economic situation, business operations