Functions of the Operating System
All the computers that we use need an operating system. It may
be a large mainframe computer running UNIX, a
desktop PC running Windows XP, or a handheld
computer running Palm OS. All these systems need
an operating system to make sure all the programs run smoothly.
The operating system is a collection
of special pieces of software that help the computer to operate normally.
The operating system has two main sets of functions:
This is the set of programs that is held in ROM and is run once
the computer first starts (boots up). The Basic
Systems software in a desktop PC allow
the computer chips to accept data from a keyboard and display text and numbers
on a VDU. Without the BIOS the computer would be effectively deaf and dumb:
unable to communicate. As extra input and output devices (peripherals) are
added then extra bits of software (called drivers)
need to be loaded so that the computer can accept data input or send data
For example, when you buy a new printer, you have to load some special software
(the printer drivers) that enable the operating system to communicate with
the new hardware.
As the computer runs, and programs save data to temporary storage
areas in RAM and then load other pieces of data from memory the operating
system has to make sure that the data is stored in proper sized chunks in
the right place so that it can be found again efficiently.
In the same way, data stored to floppy, CD-ROM or hard disk must be stored
in such a way that it can be found again quickly with no mistakes in the storage
or retrieval. The operating system offers both the user and the application
programs the chance to save data as a file; rename a file; load a new file;
and delete files.
Some operating systems have functions in them that allow them
to communicate with other computers: sharing both data and programs. The operating
systems need to make sure that different types of computers (such as desktops
and mainframes) can understand each other when connected to the same network
as well as computers and other types of hardware (such as printers, modems,
The other main job of the networked operating system is to offer system security.
This may be a simple case of including a password before the operating system
will allow a user to access the computer. Although it may include special
filters that allow only certain computers to talk to others. The networked
operating system is also able to give rights to certain users and not to others.
Now answer these questions:
out of 10 on that test