... size, the electronic computers may be subdivided into the microcomputer such as PC and APPLE, the minicomputer, the medium-computer, the large-computer (mainframe computer) such as IBM 390 and the ... modify their drawings on the screen with the help of special softwares such as :Autoship,Ship Constructor,Nupas-Cadmatic….and their drawings travelled directly to CNC machines .In the way ... as the system software and the application software. The former includes the operation system( OS) and the language system such as Assemble Language, BASIC, COBOL, C, C ++ and JAVA. Whereas the...