本标准规定并分类了软件可靠性方面的度量。它扩大了现有标准的范围；修订版包括可靠性的以下方面:软件的可靠性、可用性和可维护性。本标准适用于任何软件系统；特别是，它适用于任务关键型系统，其中高可靠性、可用性和可维护性至关重要。这些系统包括但不限于军事作战、太空任务、空中交通管制、网络操作、证券交易所、自动取款机和航空订票系统。

This standard specifies and classifies measures of the software aspects of dependability. It is an expansion of the scope of the existing standard; the revision includes the following aspects of dependability: reliability, availability, and maintainability of software. The applicability of this standard is any software system; in particular, it applies to mission critical systems, where high reliability, availability, and maintainability are of utmost importance. These systems include, but are not limited to, systems for military combat, space missions, air traffic control, network operations, stock exchanges, automatic teller machines, and airline reservation systems.