An Introduction to the computer
What is an operating system?
An operating system is a set of software programs, which provide an interface between the user machines.
Function of an operating system
Al manery management whenever any program is executed or any job is run it has be loaded into memory first, But before your program is loaded into memory the CS has to check any memory is free to gibe allocated to your fob and after the execution of your program the allocate memory is freed so that it can be allocated job.
BI CPU Management: The CPU does the actual processing of the jobs or programs. The CPU gets the job or program form the memory and processing. It after processing the job, the cup to the various jobs this function is called kip scheduling.
CI Disk Management: Whenever the users need to retrieve any files form the disk they need not bother about how and where the files are stored. It is the job of the operating system to keep a track of all the file addresses on the disk and retrieves them as and when required.
DI Input/Output Management: The computer system is attached to many peripheral devices like the keyboard, printer, mouse etc. It is OS which performs the task of co-ordination all the input and output devices.
EI User Interface: The machine understands only the language of '0' and '1' and the cannabis that are as a user give to it are in English like language. There has user and the machine to translate the English like commands into machine language and vice versa. It is the Os, which acts a bridge between the user and machine.
Single user and Multi User Operating system
A single user operating system is one, which supports only a single use at one time. Where as a multi-user operating system supports a number if users at one time. Examples, of multi user operating system are Unix, XENIX; the latest versions of does are also multi-use where as the earlier various are single users. File security is required in a multi user operating system.