Determine the types of software
There are two types of software today: Application and systems.
Meaning of the two changes computer to computer. As we concentrate on large computers, servers, we define application programs as those run by ordinary users, like email, word processing, simulation programs, spreadsheet, etc. Systems programs are used to control hardware to make the computer easy to use, secure and more efficient. Systems software include language translators (compilers, assemblers), operating systems, linkers, libraries, loaders. They are used by systems people who have special privileges (access rights) to use computer. This distinction is enforced by today's computers in the form of hardware control states: user and system states. Application programs are run in user state and if they try to run system software in this mode an interrupt (exception) is generated. Program is terminated. System programs are run in the system state.