In the software product development,a special attention should be paid to the usability of the product while realizing its functionality. Usability pertains to the user's view of the quality of a pro-duct ,which is the synonym of the quality in use. It is one of the critical factors to the success of the pro-duct. In order to improve the usability of software products ,we must first make usability visible. Thus a kind of objective ,uniform and quantitative measurements for usability is in great need. The Common In-dustry Format for usability testing is a standardized test for software usability,which is also called CIF test for short. It is the main contribution of the IUSR project initiated by the US National Institute of Standards and Technology (NIST). The CIF Test is based on a carefully designed evaluation procedure and an appropriate metrics. It enables suppliers and purchasers of software products measure the usabil-ity of the products in an objective and quantitative way,therefore promote the emphasis on products'usability. After giving the concept of software usability,this paper describes the IUSR project and its main contribution-Common Industrial Format for usability testing. The authors' experiences in using the standard are discussed finally.
