What is Linux?

Components

Linux consists of several different components discussed below.

Components

The following are essential components or subsystems in Linux that work together to ensure the operating system functions effectively:

1. Boot loader

A boot loader or manager is a program located in the program memory that executes when an application requires reloading, which helps in the boot process. It is primarily a pop-up splash screen that eventually goes away to boot into the OS.

2. Daemons

Daemons, also called background processes, ensure the proper functioning of the OS. They start up once you log in to the desktop. 

3. Graphical server

This subsystem controls how the graphics are displayed on your screen. The X Window System, otherwise known as X11 is the most common server for Linux. Without it, the users can only interact with Linux through a command-line interface. 

4. The init system

The init system is a subsystem that starts during the boot process to bootstrap the user space. It is mainly a background process that runs until the system is shut down. An init system, systemd, manages the boot process after the completion of initial booting by the boot loader. 

5. Kernel

The kernel is the core component of OS which manages the memory, processes, device drivers, requests for security services, and directs the CPU to perform tasks. The kernel has a separate space where the memory is allocated for processes and the location where the data is stored.

6. Desktop environment

It is the environment which users usually interact with. Several desktop environments like Cinnamon, Mate, Pantheon, and Enlightenment exist. Each environment includes built-in applications such as configuration tools, games, web browsers, and file managers.

Applications

Following are the applications of the Linux operating system.

• Servers: Widely used in web servers, database servers, and application servers due to their stability, security, and performance.

• Development: Preferred by developers for programming, testing, and deploying software, especially in open-source projects.

• Embedded systems: Due to their lightweight and customizable nature, embedded systems power devices like routers, IoT devices, smart TVs, and automotive systems.

• Cybersecurity: Used in ethical hacking and penetration testing tools like Kali Linux.

• Education: Provides free and open-source software for learning and academic research.

• Supercomputing: Operates on most supercomputers worldwide, supporting high-performance computing tasks.

• Desktop use: Offers user-friendly distributions (e.g., Ubuntu, Linux Mint) for everyday computing needs.

• Cloud computing: Powers major cloud platforms and virtualization technologies like Docker and Kubernetes.

• Scientific research: Supports data analysis and simulations in scientific and research domains.

Linux distributions

Linux has different versions to match the users’ needs. These versions are called distributions. Almost every distribution of Linux can be downloaded and installed for free. 

The most popular Linux distributions include:

• Debian

• Red Hat

• SUSE Enterprise

• Fedora

• Ubuntu

• Linux Mint

• Elementary OS

Some distributions offer modern user interfaces (such as Elementary OS and Gnome’s Pantheon), while others stick to a traditional desktop environment. Some server distributions, such as Ubuntu and CentOS, are free, while others, such as SUSE and Red Hat, are paid. 

Choosing the most suitable distribution depends entirely on whether you prefer a server or desktop and a modern or a traditional desktop interface.

Linux installation

The typical installation of Ubuntu Linux is as follows:

1. Preparation (Installation requirements)

2. Wireless setup (Network connection)

3. Hard drive allocation (Dual boot or install over an existing Linux version)

4. Location setup

5. Keyboard selection

6. User setup (Username and password)

Once the installation is completed, reboot the system, and you are ready.

Software installation on Linux

Applications are easy to install, just like the operating system itself. Each distribution has a centralized App Store where the applications can be installed easily. SUSE has AppStore, elementary OS has AppCenter, Ubuntu Linux has GNOME Software, and some other distributions are based on Synaptic.

Each of the centralized tools depends on a GUI (Graphical User Interface). However, the command-line interface can be used for installation in GUI-less servers, which is easier and faster than desktop GUI-based management tools. 

Note: Learn more about CLI and GUI differences from our Answer: CLI vs. GUI

Debian, Ubuntu, Mint and others

Linux Mint, Ubuntu, and all Debian-based distributions use .deb files and dpkgA package manager for Debian-based systems. for package management. To install applications from a repository, use the apt command. To install applications from .deb files, use the dpkg command.

• Using the apt command:

• Using dpkg the command:

Use dpkg if the application you want to install is available as .deb download.

Match the answers

Try out the following exercise to test your understanding of Linux:

Conclusion

In conclusion, Linux is an open-source OS widely used across industries and has gained significant popularity over the years due to its security, versatility, and community-driven developmental model. Linux distributions offer a wide range of operating systems to choose from, each with its own perks and drawbacks.