Options strategies allow traders to profit from movements in the underlying assets based on market sentiment (i.e., bullish, bearish or neutral). In the case of neutral strategies, they can be further classified into those that are bullish on volatility, measured by the lowercase Greek letter sigma (σ), and those that are bearish on volatility. Traders can also profit off time decay, measured by the uppercase Greek letter theta (Θ), when the stock market has low volatility. The option positions used can be long and/or short positions in calls and puts.