Closes are NSE's end-of-day figures; open interest is in units of the underlying and Δ OI is its change against the previous session. Implied vols are solved with Black-76 on the expiry's forward from put-call parity (the strike where call and put premiums are closest), so no interest rate assumption sits in the forward; an option whose close is at or below its intrinsic value has no vol and is shown as such. Shaded cells are in the money. The expected move is the at-the-money call plus put: what the market charges for a straddle, not a forecast. Max pain is the settlement level at which every open call and put together would pay out least, weighted by open interest. Clicking a call or put cell adds it as a leg; the tray hands the legs to the builder. Live quotes during the session are shown to the owner from the recorder; everyone else sees the end-of-day figures.