The largest Unix platforms, measured by their prevalence, influence, and relevance in the IT world in 2025, include both traditional Unix systems and Unix-like operating systems, which dominate server environments, data centers, cloud infrastructures, and development ecosystems.
Linux is the most dominant Unix-like platform because it is open source, flexible, and widely used. Among the distributions, the following stand out:
Ubuntu: Canonical’s Ubuntu is the most popular choice for servers, cloud (e.g., AWS, Azure), and developers. With LTS versions (e.g., Ubuntu 22.04, 24.04), it offers stability and broad community support. Approximately 40% of cloud workloads run on Ubuntu (estimate based on web data). It is used for web servers, AI development, and containers (Docker, Kubernetes).
Red Hat Enterprise Linux (RHEL): RHEL dominates in enterprise environments, especially in the financial and healthcare sectors, thanks to support contracts and certifications (e.g., for SAP). Red Hat’s OpenShift is the leader in container platforms. Approximately 30% of Fortune 500 companies use RHEL.
Debian: Known for stability and open-source purism, Debian is the basis for many derivatives (including Ubuntu). It is preferred in server environments and for research purposes, with a strong community.
CentOS Stream / Rocky Linux / AlmaLinux: Following the discontinuation of CentOS 8 in the traditional sense (2021), these RHEL-compatible alternatives are relevant for companies looking for free options. Rocky and AlmaLinux are gaining popularity in data centers.
macOS: Apple’s macOS, based on the Unix-certified Darwin, is the largest Unix platform in the consumer sector. With a market share of approximately 20% for desktop operating systems (as of 2025), it is popular with developers because it combines Unix tools (e.g., Bash, Zsh) with a polished GUI. macOS dominates in creative industries (design, video) and is a developer favorite thanks to Homebrew and Xcode. Its BSD roots make it a true Unix system, even though it is proprietary.
Free Unix derivatives such as FreeBSD, OpenBSD, and NetBSD are big in specialized areas:
FreeBSD: Valued in server environments (e.g., Netflix, WhatsApp) for its stability and performance. ZFS file system support makes it attractive for storage solutions. FreeBSD has approximately 5-10% market share in Unix servers.
OpenBSD: Focused on security, it is the choice for firewalls and highly secure systems. Its small size (niche market) is offset by its influence in security circles.
NetBSD: Known for portability, it runs on exotic hardware but has less commercial relevance.
NetBSD: Known for portability, it runs on exotic hardware but has less commercial relevance.
Solaris / illumos: Oracle’s Solaris, once a Unix heavyweight (Sun Microsystems), is in decline but remains relevant in the financial and telecommunications sectors (e.g., for SPARC hardware). The open-source variant illumos is being further developed in niche markets. Solaris‘ market share is below 5%, but its historical significance (e.g., ZFS) remains.
IBM’s AIX (on Power architecture) and Hewlett-Packard’s HP-UX are proprietary Unix systems that are used in large companies (e.g., banks, insurance companies) for their robustness. AIX has advantages in big data workloads (e.g., IBM Watson), while HP-UX runs on older mission-critical systems. However, both are losing market share to Linux because they are expensive and less flexible.
Linux distributions (Ubuntu, RHEL, Debian) are the undisputed market leaders because they are open source, cost-effective, and optimized for cloud, AI, and containers. macOS dominates in the developer and creative sectors, while BSD variants and traditional Unix systems (AIX, Solaris) survive in specialized, often legacy-oriented environments. The influence of Unix remains ubiquitous through POSIX standards and tools (e.g., Bash, grep), even in modern platforms such as Kubernetes. Data from web sources (e.g., Stack Overflow surveys, cloud market analyses) confirm Linux’s dominance, while proprietary Unix systems are shrinking.