A stock of a corporation signifies ownership in the corporation. A single share of the stock represents a claim on fractional assets and earnings of the corporation in proportion to the total number of shares. For example, if an investor owns 50 shares of stock of a company that has in total 1000 outstanding shares, the investor (or shareholder) would own it and have claim on 5% of the company's assets and earnings.
Stocks of a company can be traded between shareholders and other parties via stock exchanges and organizations. Major stock exchanges include the New York Stock Exchange, NASDAQ, London Stock Exchange Group, Shanghai Stock Exchange, and Hong Kong Stock Exchange. The prices which a stock is traded at fluctuate, essentially, due to the law of supply and demand. At any one moment, the supply is the number of shares that are in the hands of public investors...