Implied volatility is the market's expectation of how far BANK NIFTY will move, backed out of live option prices on the NSE chain. This page shows three cuts of it: the IV smile, which plots call and put IV across strikes for one expiry; ATM IV through the session; and the term structure, which plots at-the-money IV across expiries. Higher IV means richer premiums and a wider expected range.
BANK NIFTY tracks the most heavily traded banking stocks and moves faster than the broad market, so its option data swings harder through the session. The shape matters as much as the level — downside puts usually price above upside calls, and that asymmetry is the volatility skew, a read on demand for crash protection. An inverted term structure, where the nearest expiry carries the highest IV, points at a near-term event. IV is an expectation, not a direction, so read it beside the option chain and open interest linked above.