In Simple word Accreditation defines as “to give trust or confidence to: to vouch for; to recommend; to furnish with credentials, as an envoy or ambassador”.
According to ISO/IEC 17011 Accreditation means: Third–party attestation related to a conformity assessment body conveying formal demonstration of its competence to carry out specific assessment tasks.
It is a formal recognition by an independent body, generally known as an accreditation body, certifies Conformity Assessment Body to be capable and competent. Accreditation is not obligatory but it adds another level of confidence, as ‘accredited’ means the Conformity Assessment Body has been independently checked to make sure it operates according to international standards.
As per International Organization for Standardization (ISO) Accreditation is not compulsory, and non-accreditation does not necessarily mean it is not reputable, but it does provide independent confirmation of competence.
WAS accreditation of the Conformity Assessment Bodies (CABs) conveys formal demonstration to carry out specific certification, inspection, registration verification/validation, assessment, testing and calibration. This independent assessment and recognition of Conformity Assessment Bodies (CABs) may allow the accredited organizations tests, inspection reports and certificates to be recognized as equivalent to organizations in other countries.