Various functions of the operating system

Following are some of important functions of an operating System.
Booting: Booting is a process of starting the computer. It checks the computer and
makes it ready to work.
Memory Management: Operating System does the following activities for memory
management:
 Keeps tracks of primary memory, i.e., what part of it are in use by whom, what
parts are not in use?
 Allocates the memory when a process requests it to do so.
 Deallocates the memory when a process no longer needs it or has been
terminated.
Loading and Execution: A program needs to be loaded in the main memory before it
can be executed. Operating system provides the facility to load programs in memory
and then execute it.
Data security: The operating system protects the data stored on the computer from
illegal use, modification or deletion.
Process Management: In multiprogramming environment, the OS decides which
process gets the processor when and for how much time. This function is called
process scheduling. In addition OS also provides a mechanism for process
synchronization, process communication and deadlock handling.
Device Management: An Operating System manages device communication via
their respective drivers. It does the following activities for device management:
 Keeps tracks of all devices using I/O controller.
 Decides which process gets the device when and for how much time.
 Allocates the device in the most efficient way.
 Deallocates devices.

File Management: A file system is normally organized into directories for easy
navigation and usage. These directories may contain files and other directions.
Providing interface: User interface controls how you input data and instruction and
how information is displayed on screen. The operating system offers two types of
the interface to the user:
 Graphical-line interface: It interacts with of visual environment to
communicate with the computer. It uses windows, icons, menus and other
graphical objects to issues commands.
 Command-line interface: it provides an interface to communicate with the
computer by typing commands.
Security - By means of password, encryption/decryption and similar other
techniques, it prevents unauthorized access to programs and data.
Control over system performance - Recording delays between request for a service
and response from the system.
Job Accounting - Keeping track of time and resources used by various jobs and
users.
Error detecting aids - Production of dumps, traces, error messages, and other
debugging and error detecting aids.
Coordination between other software and users - Coordination and assignment of
compilers, interpreters, assemblers and other software to the various users of the
computer systems.