The Term of USABILITY IS Used to Indicate the Degree of Convenence of A Specific Object in the Process of Use to Achieve A Specific Goal. This Term IS Somewhat Different from the Concept of Ergonomics, Primarily in that Latter Focuses on the Appearens of the Object. Whereas, USABILITY CHARACTERIZES The LEVEL of Simplicity of Control, As Well as the Pressence of All the Necessary Functions.