What is Linux

Linux is a multiuser and multitasking operating system. It is an open-source operating system. It is one of the most widely used operating systems.

Linux operating system

A computer consists of many hardware devices, such as a keyboard, mouse, monitor, hard disk, motherboard, CPU, RAM, etc. An operating system is a program that allows us to interact with all the hardware devices and use them for productivity-related tasks. It controls and manages all hardware devices at our command. We can provide these commands by selecting menus, clicking icons, or tying text commands.

Linux is an operating system. It contains two or three layers: Kernel, Shell, and Desktop.

with and without kernel

Let us understand these layers in detail.

The Kernel

The kernel is the bottom layer of the Linux operating system. It directly controls computer hardware. It provides many features and functions. It is responsible for the following things.

Process management: - It determines which processes can use the CPU and for how long.

Memory management: - It allocates a portion of memory to each running application and process and actively monitors it.

Driver management: - A driver is a piece of code that works inside the kernel as a bridge between the hardware device and the application. An application can access a hardware device through it.

System calls:- A system call is a service request. The Shell and Desktop use them to access hardware devices.

The Shell

The Shell is the middle layer. It provides an interface to execute commands. It includes command line tools, daemons, and processes that run in the background and communicate with the kernel to perform their jobs. If the desktop is not available, it works as the top layer. If the desktop is available, it works as the middle layer.

The Desktop

The Desktop is the top layer. It includes the GUI interface. It makes management easy but increases processing overhead. It is optional.


Linux is available in many variations. The Server and Desktop are the two main variations.

server and desktop versions

The Server variation is optimized for performance, speed, scalability, and security. It does not include the Desktop layer. It is mainly used on server systems.

The Desktop variation is optimized for accessibility, usability, and easy management. It includes the Desktop layer. It is mainly used on workstations and personal computers.


multi user

Linux is a multiuser and multitasking operating system. A multiuser and multitasking operating system allows many users to log in and perform multiple tasks simultaneously.

Open-source operating system


Linux is the largest open-source software project in the world. You can run, read, modify, and redistribute its source code. It is released under the GNU General Public License. GPL license allows you to sell the modified code as long as you sell it under the same license.

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