The operating system is the most important program that run on the computer every general purpose computer must have an operating system to run other program operating system perform basic such as recognising input from the keyboard sending output to the display screen keeping track of file directories on the disk and controlling peripheral devices such as described and printers for large system the operating system has given greater responsibilities and power it make sure that different program and user running at the same time do not interfere with each other operating system is also responsible for security and showing that unauthorised user do not access the System Operating System providers software platform on the top of which other program called application program can run the application program must be written to run on the top of a particular operating system
Functions of an operating system
- In a multitasking Operating System where multiple program can be running at the same time the operating system determine which application should run in what order and how much time should be allowed for each application before giving another application a turn
- IT manages sharing of internal memory among the multiple applications
- it handle input and output to to and from attach hardware devices such as hard disk printer and dial up port
- it send message to each application for interactive user about the status of the operation and any error that may have occurred
- it can offload the management of what are called batch job so that the initiating application is free from this work
- on the computers that can provide parallel processing on operating system can manage how to divide the program so that it run on more than one processor at a time.
