Introduction to Operating System(OS)

You may have heard about or used different Operating Systems like Windows, MacOS or Ubuntu. Have you ever thought what exactly an Operating System is? The short and straightforward answer is — It is a part of system software which is responsible for managing the use of hardware by other system software and all application software.
You can imagine an OS as a conductor of an orchestra, who sets the tempo for the music, signals different instruments when sould they play, controls the volume of the individual sections of the orchestra, and so on. Similarly, the OS allocates the computer's components to different programs and synchronizes their individual activities so that the programs execute in perfect harmony.

System Software

The term System Software has been used earlier in this blog, so let us understand what it means.
System Software provides the general programming environment to the application programmers so that they can create the applications which best suits their client's needs.

As described earlier, an OS is a part of system software. Therefore, different operating systems provide different programming environments. That is why you often see multiple download options for the same software on various websites.

before diving deep into the characteristics and functions of OS one should know about the need of OS.

Need of an OS

Do you know that an OS is essential but not mandatory to perform certain tasks on a computing system? For example, if you need to read from or write to a disk device, you can do so without an OS. However, you would then have to implement the entire file system by yourself.
The OS provides a set of common programs and services that all application software uses to interact with the hardware, so we do not need to implement them separately for every application.
Although many computer systems, such as embedded systems, do not require an OS because they run simple, dedicated applications (for example, in microwaves or washing machines), an OS becomes necessary in broader and more complex systems such as personal computers.

Functions of OS

Though there is no complete argument about the exact set of functions required for an OS it changes from one OS to another but we can discuss about the general functions of an OS which are:

• Device management
• Process, thread and resource management
• Memory management
• File management

Device Management

A computer system is incomplete without I/O, storage, processing, and communication devices. An Operating System (OS) is responsible for managing all of these devices and ensuring their proper allocation and sharing among processes.

Some aspects of device management are common across all devices, while others are specific to particular device types. Based on this distinction, device management in an OS can be divided into two types:

• Device-Dependent Functions – Also known as device drivers, these implement the aspects of device management that are unique to each specific device type.

• Device-Independent Functions – These provide a general framework or environment within which device-dependent drivers operate. They handle common tasks such as buffering, error handling, protection, and device naming.

Below figure shows how the devices communicate with device dependent and independent part of the device manager.