Any one who has invested their money in the stock market for appreciable lengths of time, understands that their investments will go up and down in value. This happens not just daily but hourly and sometime minute by minute. There are no guarantees, one way or another.
The Certainty Of Change
These cyclical swings in value happen with fundamentally sound investments or not. The share prices of the biggest, high quality blue chip companies in the world can go down "in sympathy" with everything else, and stay there should the news of the period be negative enough.
When changes occurs in the stock market, it's commonly referred to as a bull or bear market. In "bull markets" overall prices go up, and in "bear markets" prices go down.
External, and completely unrelated events can have a profound impact on the direction of stock prices. Economic reports, Federal Reserve meetings, company earnings announcements and news events all impact stock markets.
The price of the overall stock market is often measured by their "indices". These are a representative basket of company stocks, such as the Dow Jones Industrial Average, composed of 30 large companies, or the S/P 500 which is the top 500 largest actively traded companies in the U.S.
Investment And Emotions
Investors can easily get caught up in the excitement and frenzy of a roaring bull market. In the extreme, they check their stock prices every 5 minutes when positive feelings abound and begin counting their "paper profits" while envisioning exotic vacations.
And their hopes get dashed when a sudden negative turn of events swings prices in the other direction, into a bear market. When one looks at a historical stock price chart, it