VIX is the ticker of the volatility index of the S&P 500.

The Chicago Board Options Exchange (CBOE) Volatility Index projects the volatility of the S&P 500 going forward by creating a composite of the volatility priced-in (implied) on various S&P 500 options.

Since it is created using the prices of options, it serves as a gauge of market sentiment, and is often called the "fear gauge" since it will spike when the market plunges.

Investors cannot invest directly in the VIX, but in short-term futures and options ETFs and ETNs that correlate with it, such as VXX and VIXY. Investors can also get amplified exposure to the index with leveraged ETFs and ETNs that offer 2x VIX and so on.

Most trading in VIX-related securities is extremely short-term, with investors getting in and out within 24 hours, and is considered high-risk investing.

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