Study

A study is any calculation applied to price or volume data and displayed on a chart to help make sense of what the market has been doing. Moving averages, RSI, MACD, Bollinger Bands, and volume histograms are all studies. The term is basically interchangeable with "indicator," though some platforms use "study" as the umbrella word and reserve "indicator" for a narrower subset.

Under the hood, a study takes raw inputs (open, high, low, close, volume, time) and runs them through a formula, then plots the result either directly on top of the price bars (like a moving average line) or in a separate pane below the chart (like an oscillator that moves between 0 and 100). The trader picks the study, sets its parameters (a moving average's length, for instance), and the platform recalculates it automatically as new price data comes in.

The nuance that trips people up is that a study describes the past. It is built entirely from historical data, so even when it appears to "predict" a reversal or a breakout, it is really just summarizing what already happened in a way that highlights a pattern. Two studies that look completely different can be built from the same underlying price data, and adding more studies to a chart does not add more information — it just re-presents the same price history through different lenses. Some studies, including proprietary ones sold by chart-service providers, combine multiple historical price behaviors into a single calculated line or zone (for example, a projected support or resistance level), but the output is still a derivative of past price, not a guarantee of future behavior.

Traders also distinguish between lagging studies, which confirm a move only after it's underway (most moving averages), and leading studies, which try to anticipate a move (some momentum oscillators), though "leading" is a matter of degree rather than an actual look into the future.