The term software is generally used to describe all programs used by computer system. These are basically set of instructions that makes the computer operate and assist the user to do useful work.
The computer software can be generally broken down to
1) System software
2) Application packages
These are sets of programs that make it possible for the user to gain access to the computer and perform certain fundamental operations. This make the computer system easier to use. Such software is the operating system utilities and translators. Examples are Microsoft Windows XP, Windows Vista, Windows 7, Windows 8 and 8.1 and Apple Mac OS 9, Mac OX 10.0, Mac 10.1 and so on.
These are other set of programs designed to solve specific class of user’s problem and they include Word Processing, Spread Sheets, Databases and Graphical packages. Examples of such software are Microsoft Excel, Access, Word Star, Word Perfect, Lotus I, II, III and Adobe Acrobat Reader, PageMaker, PDF Reader.
An operating system is the master of programs that controls and manages the resource of a computer.
FUNCTIONS OF OPERATING SYSTEM
1) It controls the way the computer user stores programs in the memory of an auxiliary storage device such as Floppy diskettes.
2) It allows users instruct the computer to run software application program or execute commands.
3) It interprets whatever information keyed in from the keyboard or input device(s) into the computer.
4) It simplifies the creation and management of files.
TYPES OF OPERATING SYSTEM
1) SINGLE USER OPERATING SYSTEM
This is an operating system that makes the computer machine independently available to only one user at a time. They are called DISK OPERATING SYSTEM (DOS) examples are PC – DOS, MS DOS, OS 12, CP/M, DR – DOS, IBM – DOS, MS – DOS WINDOWS etc.
2) MULTI USER OPERATING SYSTEM
They are the operating system that allows more than two users to work with the computer at the same time. Examples are UNIX, XENIX, PC-MOS, WINDOWS NT and NOVEL etc.
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