ABSTRACT
Computer systems consist of a set of physical entities that perform tasks through the transmission of electrical signals and the instructions that organize this electrical activity. The physical devices are referred to as hardware because of their relative permanence, while the instructions, or operating programs, are called software because of their temporary nature. This software may be characterized into two general categories. One type of software is the set of instructions that make the computer "work" properly, or act like a computer, while the other type of software deals with the specific application with which the computer system is currently involved. The first category performs tasks such as transferring information files from one memory location to another and is called the operating system software. The other category deals with a particular application such as monitoring a process characteristic and controlling a process adjustment based on the result of a calculation that involves the monitored attribute. This type of software is called applications software. Without the operating system software a computer is just a "hunk of iron," it cannot even understand the instructions programmed within the applications program. Without the applications software the computer may have tremendous potential power but is not being applied in a useful fashion.
