Stocks, each unit of which is called a share, represent ownership of a company. Stocks, owned either directly or through a mutual fund or ETF, will likely form the majority of most investor’s portfolios. 

Frequently Asked Questions
  • What’s the most expensive stock of all time?

    The most expensive publicly-traded share of stock of all time were the Class A shares of Berkshire Hathaway (BRK.A), Warren Buffet’s conglomerate and holding company as of January 2022. They hit $487,675 per share on Jan 18, 2022. It’s important to remember that this does not mean it is the most valuable company by stock value. The value of a company’s stock, or “market capitalization,” is determined by multiplying the price of its shares by the number of its shares.

  • What is the all time high of the Dow Jones Industrial Average (DJIA)?

    As of early 2022, the all-time closing high of the Dow Jones is 36,799.65 points, which it reached on January 4, 2022. The index’s all-time intraday high was 36,952.65, reached on Jan 5, 2022.

  • What are unrealized gains and losses?

    Unrealized gains or losses represent the amount you would gain or lose if you sold your investment, often a stock, at its current value. You “realize” these gains or losses when you actually sell the investment.

  • What is the difference between preferred stock and common stock?

    When people talk about stocks, they are usually referring to common stock, which is stock that usually gives voting rights in shareholder votes. Preferred stock almost never confers voting rights, but if a company only has enough money to pay some of its dividends, it has to pay preferred stock dividends first. In addition, in the event of a bankruptcy, preferred stockholders have priority over common stockholders on company assets.

  • What’s the difference between cyclical and non-cyclical stocks?

    Cyclical stocks are those that tend to rise and fall with the broader economy, falling when the economy is doing poorly and rising when the economy is doing well. Non-cyclical, often also called defensive stocks, tend have steadier performance that do better when the economy is down are down but peak less high during boom years.

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Page Sources
Investopedia requires writers to use primary sources to support their work. These include white papers, government data, original reporting, and interviews with industry experts. We also reference original research from other reputable publishers where appropriate. You can learn more about the standards we follow in producing accurate, unbiased content in our editorial policy.
  1. New York Stock Exchange (NYSE). "Berkshire Hathaway, Inc. BRK.A." Accessed Jan. 22, 2022

  2. Yahoo! Finance. "Dow Jones Industrial Average (^DJI). Historical Data." Accessed Jan. 14, 2022.

  3. U.S. Securities and Exchange Commission. "Stocks." Accessed June 28, 2021.