Role of an operating system

• An operating system (OS) is software that controls the computer’s hardware and software resources. It allows applications to interact with the hardware on a computer. Some software can interact with hardware directly, but most software isn’t written to interact with each particular piece of hardware — the operating system therefore takes care of interacting with the hardware.
• The earliest computers did not have an OS. Every program had to include all of the code to run the computer. This made each computer program complex and difficult to create. Since then, operating systems have been developed, with part of their function being to include the code needed to run the computer. This allows for multiple applications to be written more easily to work on a common operating system rather than for individual computers.
• Whether or not the OS is custom written for a particular device, or it is a well known OS installed on a wide range of hardware including the device you're using right now, they all perform the same basic functions that keep your computer running smoothly:

  • Processor management
  • Inputs, outputs, and interrupts
  • Memory management
  • Security
• The operating system is the most fundamental piece of system software. All other software requires an operating system in place, which will:

  • Act as a platform on which the other software can run
  • Handle the operations that are common to different pieces of software running on the same system (e.g. allowing software to read and write to secondary storage devices such as a hard disk).
• Software instructs the system hardware to carry out tasks, and layers of software combine to allow the computer to carry out these tasks. Typically, the operating system interacts with hardware, provides a user interface, and supports security.
• The operating system manages resources and ensures that the software and hardware can communicate with each other, which includes processor scheduling, handling interrupts, memory management, secondary storage management, and input/output device management.
• Processor scheduling — determining the order in which processes will be executed, which allows for multi-tasking
• Handling interrupts — dealing with requests that disrupt the processor's work.
• • Memory management — recording how memory in the computer is divided and identified so that memory is allocated efficiently between processes that are running.
• Secondary storage management — tracking where files and programs are stored and which parts are available for storage, and managing files and folders based on user permissions
• Input/output device management — ensuring efficient communication with devices and managing functionality issues
• Input/output device management — ensuring efficient communication with devices and managing functionality issues
• The operating system provides the user interface, which is the means by which users of the computer interact with the computer and receive the information that it processes.
• The operating system supports the security of a device by ensuring that resources are protected from unauthorised access through the use of permissions and passwords.