Moreover, they don't have to be sectors unavailable for reading/writing information by default, sometimes potential bad sectors are label as 'non-operational'. You can find bad sectors even on new non-used hard drives. You can prevent damage by carrying out special software 'treatment' of your computer from time to time. When there are more bad sectors than allows the amount stated by the manufacturer, a hard drive stops working. The more bad blocks you have, the worse and slower your storage device operates. An unreliable or unreadable sector of an HDD is usually called a bad sector or a bad block.
