The 200-day moving average is the average closing price of a stock over its last 200 trading sessions, drawn as a line on the chart. Traders and investors use it as a quick test of the long-term trend: price above it usually means the bigger trend is up, below it means the trend is weak.
Around 200 sessions is close to one year of trading in India, so the line smooths out daily noise and shows where the stock has been over a full year. Because fund managers, analysts and retail traders all watch the same line, it often acts as support or resistance simply because so many people react to it.
Say a hypothetical stock, ABC Ltd, has been trading near ₹800 while its 200-day average sits at ₹720. If the price dips back to ₹725 and buyers step in, many traders read that as the long-term trend holding. If it closes below ₹700 for several sessions, they treat it as a warning and tighten their stop losses.
A common mistake is treating the line as an exact price. It is a zone. Price can slip below it for a day or two and recover. Another mistake is using the same setting on a 5-minute chart, where 200 candles means something completely different.
We show how to combine moving averages with price action and volume in our technical analysis course.