A binding commitment to do or give or refrain from something; “An assurance of help when needed”; “Signed a pledge never to reveal the secret”. Freedom from doubt; belief in yourself and your abilities. A binding commitment to do or give or refrain from something; “An assurance of help when needed”; quality assurance system is said to increase customer confidence and a company’s credibility, to improve work processes and efficiency, and to enable a company to better compete with others.