What is an Operating System? Features and Functions

An operating system (OS) controls all the other software on a computer. Operating systems also control and manage input and output to all hardware on a computer, including keyboards, displays, disk drives, network devices, and printers. All these other system parts are known as the computer’s “platform”.

If we were to break this down in very simple terms, the operating system is a piece of software that sits between the application software and the machine itself. It takes the application program commands and breaks them into small pieces that can then be executed, managed and stored efficiently. The operating system will also take instructions from the application software and put them back together in a manner that is consistent and understandable to the program.

Most operating systems are built on top of an Operating System kernel. This is the “engine” that drives the entire operating system. It is what allows the computer to work at all. It is the interface that allows you to send commands to the computer. The operating system kernel will interpret and manage the application program commands in a fashion that guarantees that the computer will do what it is intended to do.

If you are like most other Windows users, you use a variety of tools on your operating system. For example, you might use Notepad to write and save your notes. You might use File Explorer to view documents and folders. You might use the Windows Command Prompt to execute any programs you want to run. And you might use Chrome to access the Internet and browse through websites.

Features of an Operating System

User Interface

The operating system provides a user interface to interact with the system. There are two types of user interfaces: Command Line Interface (CLI) and Graphical User Interface (GUI). A CLI allows the user to enter commands through a command prompt, while a GUI provides a visual interface with icons, buttons, menus, and windows.

Memory Management

The operating system manages the memory resources of the system. It allocates memory to the running programs and deallocates memory from the terminated programs. The OS also manages the virtual memory, which is a technique of using the hard disk as an extension of RAM.

Process Management

The operating system manages the processes in the system. A process is an executing program or a part of a program. The OS creates, schedules, and terminates processes as per the user’s request.

File System Management

The operating system manages the files and directories in the system. It provides a hierarchical file system structure and supports various file systems such as FAT, NTFS, and EXT.

Device Management

The operating system manages the input/output devices of the system. It controls the communication between the devices and the programs. The OS also provides device drivers to interact with the hardware devices.

Security

The operating system provides security features to protect the system from unauthorized access and malicious attacks. It provides user authentication, access control, encryption, and firewall services.

Networking

The operating system provides networking services to connect the system to the network. It supports various network protocols such as TCP/IP, HTTP, FTP, and SMTP.

Functions of an Operating System

Resource Allocation

The operating system allocates the system resources such as CPU, memory, and input/output devices to the running programs. It ensures that each program gets a fair share of the resources and does not starve other programs.

Multitasking

The operating system supports multitasking, which means running multiple programs simultaneously. It schedules the processes in such a way that each program gets a fair share of the CPU time and does not cause a system hang or crash.

Interprocess Communication

The operating system provides facilities for interprocess communication (IPC) between the processes. IPC allows the processes to communicate and share data with each other.

Error Handling

The operating system handles the errors and exceptions in the system. It provides the user with error messages and diagnostic information to help them identify and resolve the errors.

System Call Interface

The operating system provides a system call interface, a set of functions the programs can use to access the OS services. The system call interface acts as a bridge between the user programs and the kernel.

System Configuration

The operating system allows the user to configure the system settings such as date and time, display settings, network settings, and power settings. The user can also install and uninstall the software programs and device drivers.

System Monitoring

The operating system provides facilities for system monitoring and performance analysis. It allows the user to monitor the system resources and the performance of the running programs. The OS also generates system logs and performance reports for troubleshooting and optimization.