A moving average smooths out a noisy price series by continuously averaging the most recent closing prices, producing a single line that follows the trend. As each new bar arrives, the oldest drops out and the average moves along, which is where the name comes from.
SMA vs EMA
- Simple Moving Average (SMA) — averages the last N closes with equal weight. Smooth and stable, but slower to react to a sudden turn.
- Exponential Moving Average (EMA) — weights recent prices more heavily, so it turns faster and tracks the latest action more closely, at the cost of more false wiggles.
Traders use moving averages to define trend direction (price above a rising average is a simple uptrend read), as dynamic support and resistance, and in crossover setups where a faster average crossing a slower one flags a possible shift. Related tools include VWAP, a volume-weighted intraday average. Like all indicators, moving averages lag by design, because they are built from past prices; they describe the trend, they do not predict it.