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Husbands endure Saturday-evening dinners with their in-laws in exchange for a Sunday of uninterrupted football. Kids pass up watching television to take out the trash and wash dishes because they want spending money. And parents extend Friday night curfews as a reward for good behavior during the week.

Life is about trade-offs. So is investing.

The investment trade-off is between risk and return. Getting a return on your investment means accepting risk, at least to some extent. But what, exactly, is risk? And how much of it can you tolerate?

This course reviews the types of risk involved in investing, and shows you how to develop your philosophy about investment risk.

Two general risks

Investors face two general types of risk.

First, there's the risk of losing money in the short term. Over the last 80 years, the stock market has produced annualized returns of nearly 10%. But about one of every four years during that period was a down one for the market.

And over shorter time periods -- a few weeks or months -- investments can be even more volatile.

Investors focus almost exclusively on short-term risk. It's easy to do. Every day you hear about how the market is doing. And if that's not enough, you can check your stock prices throughout the day.

Don't let volatility get the best of you, though. If you do, you'll virtually ignore the second and perhaps even greater risk that comes with investing: the risk that you won't meet your goals.

How can obsessing about volatility get in the way of your goals? It may cause you to invest too conservatively. Volatility also may lead you to buy or sell an investment based on short-term performance rather than on how this purchase or sale will help you reach your goal. In short, volatility can prevent you from seeing the forest for the trees.

Weigh how important reaching your goal is against how much short-term volatility you're willing to accept.

Contributors to volatility

When thinking about short-term volatility and your acceptance of it, consider some of the specific risks associated with investing. Think of volatility as the byproduct of risk: When a hidden risk manifests itself, volatility ensues. But by diversifying your portfolio, you can reduce the impact of any one of these risk factors, and therefore limit your short-term volatility.

Market risk. Market risk comes with exposure to a particular asset class or sector, such as U.S. equities or technology stocks. It's the threat of the entire market losing money. That can happen if investors think that the U.S. stock market is selling well above its prospects, for example, or that technology stocks as a group are going to face slower growth.

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To limit market risk, diversify into various markets and sectors. By doing so, you're eliminating your portfolio's dependence on a single market.