What is Linux? | SUSE

What is Linux?


Join us in this review of ‘What is Linux‘, tracing its evolution, the significance of open source, and SUSE’s role in this journey. From humble origins to future aspirations, we spotlight the challenges and milestones that define Linux’s legacy, rooted firmly in the ethos of open-source collaboration.

Table of contents:

Introduction to Linux

Understanding Open Source

Linux Distributions

Linux internals

Linux in the Enterprise

Future Trends and Developments

SUSE, Linux and the Open-Source movement



Introduction to Linux

Linux is an open-source kernel, similar to Unix, that forms the base for various operating system distributions. While the term “Linux” is commonly used to refer both to the kernel and the entire operating system built around it, a more precise term is “GNU/Linux”. This name highlights the combination of the Linux kernel with the extensive tooling provided by the GNU Project, turning something that was just a kernel into a full-fledged operating system.

Linux stands as a testament to the power of community collaboration. It has significantly shaped the software landscape through the combined efforts of tens of thousands of developers, leading to a broad collection of software. For those interested in a detailed history, we recommend this Wikipedia entry.

Given the recent turbulence in the Linux landscape, it makes sense to take a step back and look at what is Linux: its beginnings, its core structure, and its main milestones.

Going over its journey and key achievements will give us a clearer idea of how to better deal with the challenges coming ahead, and the potential developments that could help shape it for the next 30 years.

Understanding Open Source

Beyond its technical excellence, one of the key achievements of the GNU/Linux project has been the widespread adoption of the open-source development model, where developers share code for others to use, rebuild, and redistribute.

The legal foundation for this approach is primarily provided by the GNU Public License and other OSI-compliant licenses. These licenses have nurtured a broad open ecosystem and facilitated the growth of a plethora of software solutions, fostering a vibrant and innovative ecosystem.

It’s vital to remember that a genuine commitment to open source is a core reason for the success of GNU/Linux compared to other projects. It has even surpassed its closed-source counterparts in success. This is a testament to countless individual contributors and companies. And it’s a legacy that we should safeguard, no matter what challenges lie ahead.

Companies built on open source should always remember their roots. They’ve stood on the shoulders of giants, so recent events, like HashiCorp’s sudden license change or Red Hat’s moves to severely limit access to their distribution source code, endanger the true spirit of open source.

Linux Distributions

The initial complexity of configuring and compiling a Linux kernel and adding on top all the necessary GNU exiting tooling to build a running system (partitioning, file systems, command interpreters, GUI, …) led to the birth of the so called Linux Distributions.

A Linux Distribution is a way of packaging all the required software, together with an installer and all the necessary life-cycle managing tooling to be able to deploy, configure and keep updated over time a GNU/Linux environment.

The first really comprehensive distribution is considered to be SLS with the first distribution as we know them now being Slackware published in 1993. Founded in that very same year, SUSE was the first company to introduce an enterprise Linux distribution back in 1995.

There’s a very interesting timeline covering the origins and evolution of all linux distribtions available in Wikipedia

Linux internals

Linux Kernel

The Linux kernel is the central component of the Linux operating system, bridging software applications with the computer’s hardware. When a program or command is executed, it’s the kernel’s duty to interpret this request for the hardware. Its primary functions include:

  • Interfacing with hardware through modules and device drivers.
  • Managing resources like memory, CPU, processes, networking, and filesystems.
  • Serving as a conduit for applications and facilitating communications through system libraries, user space libraries or container engines.
  • Providing support for virtualization through hypervisors and virtual drivers
  • Overseeing foundational security layers of the OS.

By 2023, the Linux kernel is based on more than 30 million lines of code, distinguishing it as the largest open-source project in history and with the broadest collaboration base.

Command-Line Interface (CLI)

Echoing Unix’s design, from which Linux draws inspiration, the primary interaction mode with the OS is through the Command-Line Interface. Of the various CLIs available, BASH is the most widely adopted.

Graphical User Interface (GUI)

For those preferring visual interaction, Linux offers diverse GUIs. Historically rooted in the X-Windows system, there’s a noticeable shift towards modern platforms like Wayland. On top of these foundational systems, environments like GNOME, KDE, or XFCE serve as comprehensive desktop interfaces. They provide users with organized workspaces, application launching capabilities, window management, and customization options, all while integrating seamlessly with the core Linux kernel.

Linux Applications and Software Ecosystem

Understanding an operating system involves not only grasping its core mechanics but also the myriad applications it supports. For GNU/Linux, an intrinsic part of its identity lies in the vast array of software that’s been either natively developed for it or ported over. This wealth of software stands testament to the versatility and adaptability of Linux as an operating system platform.

  • Diverse Software Availability: Linux boasts a plethora of applications catering to almost every imaginable need, from office suites and graphics design tools to web servers and scientific computing utilities.
  • Package Managers and Repositories: One of the distinctive features of Linux is its package management systems. Tools like apt (used by Debian and Ubuntu), dnf (used by Red Hat-based systems), zypper (for SUSE/openSUSE), and more recently, universal packaging systems like flatpak, enable users to easily install, update, and manage software in a confined model that simplifies portability across distributions. These package managers pull software from repositories, which are vast online libraries of pre-compiled software and dependencies.
  • Emergence of Proprietary Software: While open-source software is the cornerstone of the Linux ecosystem, proprietary software companies have also recognized its value. They understand the importance of providing compatibility and packages for Linux platforms, further expanding the user base.

Linux in the Enterprise

Originally started as a hobby and a collections of research projects and tools, the potential of GNU/Linux as a platform for enterprise workloads rapidly became apparent. The closed nature of Unix, coupled with the fragmentation among Unix-based solutions back in the day, opened doors for Linux. This was particularly prominent as Linux exhibited its compatibility with widely adopted tools, such as GNU’s GCC, bash or the X-Windows system. Moreover, the dot-com bubble further spotlighted Linux’s prowess, with a surge in Linux-based services driving internet businesses that started to transform the IT landscape and set the roots for the Linux dominance in the server space that we can see today.

And how did it make its way from a hobbyist’s playground to a powerhouse in the enterprise world?

  • Open-Source Advantage: The open-source model became an invaluable asset in the corporate realm. As Linux showcased, the more developers and specialists that could access, review, and enhance the code, the higher the resultant software quality. This open-review mechanism ensured rapid identification and rectification of security concerns and software bugs.
  • Emergence of Enterprise Vendors: Enterprise solutions providers, notably Red Hat and SUSE, went beyond mere software distribution. These vendors began offering comprehensive support packages, ensuring businesses received consistent, reliable assistance. These packages, underpinned by enterprise-grade Service Level Agreements (SLAs), encompassed a wide range of offerings – from hardware and software certifications to implementation of security standards and legal assurances concerning software use.

Today, Linux reigns in the enterprise ecosystem. It is not only the go-to platform for a vast majority of new projects but also the backbone for the lion’s share of cloud-based services. This widespread adoption is a testament to Linux’s reliability, scalability, and adaptability to diverse business needs.

Despite having celebrated its 30th anniversary, Linux’s journey of expansion and adoption shows no signs of deceleration:

  • Containerization Surge: Modern software deployment has been revolutionized by containerization, with Linux playing a pivotal role. Containers package software with its required dependencies, ensuring consistent behavior across diverse environments. Linux underpins this movement, providing the foundation for technologies like Docker and Kubernetes.
  • Cloud Services Boom: The phenomenal growth of cloud services, powered by giants like AWS, Azure, and Google Cloud, has further solidified Linux’s dominance. This platform’s adaptability, security, and performance make it the choice foundation for these expansive digital infrastructures.
  • AI and Supercomputing: Linux stands at the forefront of cutting-edge technologies. Every significant AI initiative today relies on Linux. Furthermore, the top 500 supercomputers globally, including those currently under construction, are Linux-powered, showcasing its unmatched capabilities in high-performance computing.
  • IoT and Edge Computing: The proliferation of Internet of Things (IoT) devices and the growth of edge computing highlight another avenue where Linux shines. Its lightweight nature, modularity, and security features make it the preferred OS for these devices.

However, as the proverbial horizon brightens, challenges loom. While Linux has technically outpaced competitors and cemented itself as the de-facto standard for many new products and technologies, preserving its essence is crucial. The ethos of Linux and open-source, characterized by community, transparency, and collaboration, must be safeguarded. Initiatives like the Linux Foundation’s CNCF, which offers a blueprint for effective open source software development and governance far beyond just Linux, or the Open Enterprise Linux Association (OpenELA), are dedicated to keeping that spirit alive.

SUSE, Linux and the Open-Source movement

Introduction to SUSE

Originating as a German software company, SUSE has a long-standing history with Linux. It’s not only one of the earliest Linux distributions around but also one of the most preeminent advocates of the open-source philosophy.

Features and Benefits

SUSE Linux Enterprise Server (SLES) stands out for its enterprise-grade support, extensive HW and SW certifications database, robustness, and commitment to security.

SLES can be used on desktops, servers, HPC, in the cloud, or on IoT/Edge devices. It works with many architectures like AMD64/Intel 64 (x86-64), POWER (ppc64le), IBM Z (s390x), and ARM 64-Bit (AArch64).

SUSE’s Position in the Enterprise World

In the enterprise world, SLES is recognized as a reliable, secure, and innovative Linux distribution. It’s at the core of many demanding environments and powers business-critical systems, including those for SAP and the world’s largest supercomputers.

SLES isn’t just a standalone product; it’s part of a broader enterprise solutions portfolio. This includes, among others, SUSE Manager for scalable Linux systems management, Rancher Prime as a Kubernetes management platform, and NeuVector for enterprise-level Zero-Trust security for cloud-native applications.

The Open-Open Movement

Beyond its product offerings, SUSE’s commitment to the “open-open” philosophy sets it apart from other players. It embraces not only open-source but also open communities and open interoperability. This ensures that SUSE’s solutions promote flexibility and freedom while remaining true to the principles of the open-source movement.

Evidence of this commitment is visible across our entire portfolio. For instance, SUSE Manager has the capability to manage and support up to 12 different Linux distributions. Similarly, Rancher Primer doesn’t only run on SLES; it’s also compatible with openSUSE Leap, RHEL, Oracle Linux, Ubuntu, and Microsoft Windows. Additionally, it’s interoperable with major managed Kubernetes providers and public cloud vendors such as GCP, Azure, AWS, Linode, DigitalOcean, and many more. This commitment extends beyond our product lineup. SUSE also financially supports and donates software to organizations like the CNCF, as seen with K3s, and leads initiatives like the Open Enterprise Linux Association.

These initiatives highlight SUSE’s commitment to delivering solutions that promote genuine openness and user choice, while avoiding the pitfalls of single-vendor ecosystems that claim to be “open-source” yet offer non interoperable software stacks or restrict access to source code.


Over the past 30 years, this community effort has consolidated, transforming the way software is built, licensed, and distributed. Linux, now ubiquitous, continues to grow steadily, serving as the foundation for the latest IT solutions and technologies.

Now it’s time to transform how Linux distributions are built and delivered to achieve even higher levels of speed and flexibility. Initiatives like SUSE’s ALP Project aim to shape how Linux distributions will be built in the future, allowing for more use cases and scenarios, and a more flexible foundation to integrate the Linux kernel, along with the tooling and applications.

Want to join the open-open revolution? SUSE is growing and always looking for talent. Check all the open positions on our Jobs Website.

Juan Herrera Utande
Juan Herrera Utande   Head of Technical Marketing