Linux is an open-source, Unix-like operating system kernel released by Linus Torvalds in 1991. Initially started as a personal project, the kernel has expanded with the support of developers worldwide and has become usable across a wide range of computing environments. Linux is widely used not only in personal computer systems but also in servers, embedded systems, supercomputers, and mobile devices. Its release as free software under the GNU General Public License (GPL) has secured its significance in both technical and socio-technical domains.

Historical Development of Linux

Early Period: Minix and Linus Torvalds’ Contribution

The development of Linux is rooted in the Unix system architecture. In the 1980s, Minix, an operating system developed by Andrew S. Tanenbaum for educational purposes, allowed many users to gain experience with Unix-like systems. While a student at the University of Helsinki, Linus Torvalds observed the limitations of Minix and began developing a new kernel. In 1991, he released the first version of the Linux kernel and made the source code publicly accessible.

Community Involvement and Software Ecosystem

The release of Linux under the GPL enabled software developers to contribute to its evolution. This open contribution model, combined with Richard Stallman’s GNU Project, helped Linux become a complete operating system. By the late 1990s, distributions such as Red Hat, Debian, and Slackware had been developed, expanding the user base. Today, there are many active distributions, including Ubuntu, Fedora, Arch Linux, and CentOS.

Commercial Expansion and Enterprise Use

From the 2000s onward, various technology companies began integrating Linux into their infrastructures. Organizations such as IBM, Google, Oracle, and Amazon have adopted Linux-based solutions in their products. The Android mobile operating system is built on the Linux kernel and has reached a broad user base. Furthermore, Linux is the predominant operating system in the field of supercomputing, with almost all systems on the TOP500 list running Linux.

Technical Architecture and Kernel Structure

Monolithic and Modular Architecture

The Linux kernel is based on a monolithic architecture. Core system functions run integrally within the kernel, and the modular structure allows various functional components to be dynamically loaded or removed from the system. This modularity enhances adaptability to different hardware configurations.

File System and Process Management

The Linux file system hierarchy follows the traditional structure of Unix. All resources in the system are represented as files, and it supports various file systems such as ext4, XFS, and Btrfs. Process management is structured in accordance with POSIX standards, with each process identified by a unique process ID (PID). Linux supports multitasking capabilities.

Security Mechanisms

Security in Linux is maintained through user and group-level access controls. In addition to file and directory-level authorization mechanisms, kernel-level mandatory access control (MAC) systems like SELinux (Security-Enhanced Linux) and AppArmor can also be integrated. These features offer advanced controls to enhance system security.

Areas of Application and Contemporary Role

Server Systems and Cloud Technologies

Linux is a widely used operating system in server infrastructures. It is compatible with open-source services such as Apache, Nginx, PostgreSQL, and MySQL. Moreover, cloud computing technologies like Kubernetes, Docker, and OpenStack are designed to operate on the Linux kernel.

Embedded Systems and Mobile Platforms

The flexible and customizable nature of the Linux kernel facilitates its widespread use in embedded systems. From automotive systems to household electronics, Linux-based embedded software is prevalent. The Android operating system is based on the Linux kernel and holds a significant position in the mobile device market.

Scientific, Academic, and Enterprise Applications

Linux is the preferred operating system in scientific research requiring high-performance computing (HPC). The vast majority of supercomputers run on Linux. It is also extensively used in fields such as software development, artificial intelligence, data science, and cybersecurity.