01Realized and implied volatility
Realized volatility measures variation in observed returns over a selected historical window. Implied volatility is inferred from option prices using a model or methodology. It reflects pricing of future uncertainty and risk compensation, not a perfect forecast. Options give asymmetric payoffs: a call grants a right to buy, a put a right to sell, subject to strike, expiry and exercise terms. Buying an option can lose the entire premium; selling options can create much larger risks.
02Read the VIX in the right units
The VIX uses S&P 500 option prices to estimate a constant roughly 30-day expected volatility measure, quoted at an annualized rate. It is not a percentage prediction of the index’s next-day loss. A higher VIX can reflect greater uncertainty or more expensive protection. Convert annualized volatility to a shorter horizon only as a rough scale: the square-root-of-time approximation assumes a simplified return process and understates important features such as jumps and changing volatility.
03Risk is broader than volatility
Permanent capital loss, illiquidity, leverage, concentration, default and model error are risks even when recent prices appear calm. Correlations can shift during stress. A strategy that makes small profits steadily may conceal rare large losses. Read volatility together with equity breadth, credit spreads, financing conditions and the position’s payoff structure. VIX exposure through futures products also differs from holding the VIX index itself.