Operating systems are normally (1) to their manufacturers and the (2) in which they are run. Generally , when a new computer (3) is installed, operational (4) suitable to that hardware is purchased. (5) want reliable operational software that can effectively support their (6) activities. Loading (7) is only one of the operating system ’ s m any supporting (8). It consists of software modules that insulate the(9) from the hardwa re, t hus relieving the programmer of some very complex (10) of programming and making the system easier to use.