The most common kind of coding bug, and often considered the least harmful, are documentation bugs (i.e., erroneous comments). Although many documentation bugs are simple spelling errors or the result of poor writing, many are actual errors – that is, misleading or erroneous comments. We can no longer afford to discount such bugs, because their consequences are as great as ‘true’ coding errors. Today programming labor is dominated by maintenance. This will increase as software becomes even longer-lived. Documentation bugs lead to incorrect maintenance actions and therefore cause the insertion of other bugs.