It will soon be the 10-year anniversary of when, in early October 2007, the S&P 500 Index hit what was its highest point before losing more than half its value over the next year and a half during the global financial crisis.

Over the coming weeks and months, as other anniversaries of major crisis-related events pass (for example, 10 years since the bank run on Northern Rock or 10 years since the collapse of Lehman Brothers), there will likely be a steady stream of retrospectives on what happened as well as opinions on how the environment today may be similar or different from the period leading up to the crisis. It is difficult to draw useful conclusions based on such observations; financial markets have a habit of behaving unpredictably in the short run. There are, however, important lessons that investors might be well-served to remember: Capital markets have rewarded investors over the long term, and having an investment approach you can stick with—especially during tough times—may better prepare you for the next crisis and its aftermath.

Learning the jargon of financial investment can be daunting, but it can also provide you with a better way to understand the status of your investments. Here is a brief primer on some common financial terms you should know, and things you should consider when evaluating your portfolio and investment returns.

Gambling is speculation. One cannot assume any expectations based on the amount of risk one takes. You could win $50 million from a $5 lottery ticket or you could bet $50,000 and win nothing. Investing is quite different. Investing in capital markets has a positive expected return for risk taken.

Stock markets worldwide have reliably rewarded long-term investors. For example, over the past eighty years, investors who held the S&P 500 (including dividends) for at least 12 years would always have had positive returns.

Commodities, like many things that come out of Wall Street are easy to sell and hard to trust. Though the Commodities market is sometimes in vogue, they are too volatile to be held for the long-term. According to a Goldman Sachs Group Inc. study from 2016, a portfolio of stocks, bonds and commodities showed a worse return in the period from 1987 to 2015 than a portfolio of just equities and debt. They also may not be a good hedge during stock market declines: Commodities fell more than U.S. equities during the recent stock market declines in 2008, 2010, 2011 and 2015.

The reliability of investment outcomes and the relationship to performance in a diversified portfolio

The benefits of diversification is something we discuss at great length with our clients. In addition to the commonly discussed benefits of diversification: increased returns and volatility reduction; the other lost leader is the positive impact that diversification has on delivering reliable outcomes.

In a research paper by Wei Dai, PhD of Dimensional Fund Advisors, Dai identified that the most reliable drivers of expected returns, or what they call dimensions, are the premiums associated with company size, relative price and profitability. But that isn’t the end of making sound investment decisions when choosing what companies to include in a fund or which equities to include in a portfolio.