At some point you will want to reconcile the transactions you have entered with the transactions listed in a statement, be it a bank statement, credit card statement, loan statement, or any other statement. Reconciliation involves matching what you have entered with what the statement lists. If any discrepancies are found then either you or the person who created the statement have made a mistake.
To reconcile an account, first select the account, either from Accounts view or from Ledgers view. Then, either click on the Reconcile icon on the Toolbar, or select the → menu item.
A full description of this topic can be found in the Reconciliation section.