Hedging mode is an account setting that allows a trader to hold both a long and a short position on the same instrument simultaneously, tracked as separate tickets. Netting mode instead automatically combines same-instrument trades into a single net position, which is the required mode for US-regulated accounts and the default on many MT5 setups.
Which mode an account uses changes how certain strategies (like grid trading or direct hedging) need to be built, since a strategy relying on holding offsetting positions simply can't work the same way under netting.
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What Hedging a Position Actually Costs
Opening the opposite trade freezes the price, not the bill. The spread paid twice, two separate swaps, a margin discount that can be withdrawn, and the decision a hedge only postpones.