ISO 9000:2005 (the actual standard name) explains the fundamentals of quality management systems (like ISO9001) and Vocabulary used in the ISO9000 Standards and:
ISO 9000:2005 focuses on what makes up a quality management system (or QMS). In a sense, it provides the framework for a group of standards that govern how a consistent, training-driven quality system should function. This is whether it is serving a wide variety of industries (like ISO 9001) or a more specific industry like the automotive standard ISO/TS 16949. In writing a standard to govern how a quality system should broadly function, ISO lays out the basics of such a system and provides definitions and concepts that can be applied to the ISO 9000 grouping of quality systems.
This standard is useful to a fairly specific set of users. It may include organizations that may be seeking to apply multiple standards. It might also include end users that want to understand how the quality of their products or services are maintained, those who wish to gain a broader understand of terms and definitions used in ISO constructed quality systems, those who must administer an ISO quality management system in some way (such as auditors, regulators, certification bodies etc.) and those seeking to develop standards of their own that might need to harmonize with what is ISO 9000 from the overall family/grouping perspective.
The previous version of ISO 9000:2005 was ISO 9000:2000. The last 4 digits (2000), represent the year of the last revision. People often confused ISO 9000:2000 with ISO 9001:2000, which has since been updated to ISO 9001-2008
Learn about the ISO 9000 Family of Standards, including these:
ISO 9001:2008 lists requirements, while ISO 9000:2005 and ISO 9004:2009 are Quality Guidelines. People often say "ISO 9000 certified", but what they mean is they have met the requirements of the ISO 9001 standard. Read about ISO 9001...
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