What's the difference between the realized gains and losses accounts and the cross currency rounding account?

The realized gains and realized losses accounts are used to account for the conversion rate gain or loss in the ledger currency resulting from a cross-currency receipt application.

For example, if the conversion rate for a foreign currency invoice is 1.7 and the conversion rate of the payment for this invoice is 2.0, Receivables posts the difference as a gain to the realized gains account.

The cross-currency rounding account is used to record rounding error amounts created during a cross-currency receipt application. You must define a rounding error account if you create cross-currency receipts.