Indicator

An indicator is a mathematical calculation applied to price, volume, or other market data and plotted on or below a chart to help traders interpret conditions. Indicators fall into broad families: trend indicators such as moving averages, momentum oscillators such as RSI and MACD, volatility measures such as Bollinger Bands and ATR, and volume-based tools such as OBV and volume profile. All of them transform the same underlying data — past trades — into a more readable form.

For example, a swing trader's chart might show the 50-day and 200-day moving averages for trend context, RSI for momentum extremes, and raw volume bars to confirm breakouts. Each indicator answers a narrow question — is the trend up, is the move stretched, is participation real — and the trader assembles the answers into a decision.

The most important misconception to correct is that indicators predict the future; every indicator is computed from data that already exists, so they describe the present and recent past, and any forward value comes from the assumption that current conditions persist. Adding more indicators also does not add more insight when they are derived from the same inputs — five momentum oscillators will mostly agree by construction. Experienced traders typically use a small, complementary set and treat indicators as context around price and structure rather than as signal machines.