FOK is an acronym for "Fill or Kill". It's a conditional type of time-in-force order used in securities trading that instructs a brokerage to execute a transaction immediately and completely or not at all.A FOK order is useful when you want to be sure that you get the best price on your trade, but don't want the stock to sit idly in your account if it can't be filled right away. For example, imagine you're buying 100 shares of Company A at $10 per share. You could place a limit order for $10 and hope someone sells you shares at that price, but there's no guarantee. Alternatively, you could place a FOK order which would guarantee that you get the shares immediately (or not at all) – regardless of what the current market price is.Keep in mind though that because FOK orders are so urgent, they often come with significant premiums over regular market prices. So if liquidity isn't an issue, it might make more sense to use a limit order instead.
