IRIX

IRIX is a discontinued UNIX-like operating system developed by Silicon Graphics (SGI) for its MIPS-based workstations and servers. Introduced in the late 1980s, IRIX served as the standard OS on SGI’s high-end graphics machines, including the Indigo, Indigo2, Octane, and Onyx families. It was designed to deliver strong multimedia and 3D graphics performance, supporting large-scale visualization and compute workloads.

The software base of IRIX is rooted in UNIX System V Release 4 with BSD-derived features, providing a POSIX-compatible environment and a rich set of development tools. The system commonly used the X Window System for its graphical interface and benefited from SGI’s emphasis on graphics and multimedia. OpenGL, a graphics API developed by SGI, was closely associated with IRIX and became a widely adopted standard in the industry. IRIX supported multiple processors and, over time, variants included 64-bit support on capable hardware.

IRIX distinguished itself through its graphics-oriented ecosystem. It offered tightly integrated drivers and libraries for SGI’s accelerated graphics hardware, a range of specialized visualization and rendering software, and development environments tailored to professional visualization, scientific computing, and film production pipelines. Early IRIX releases used the Extent File System (EFS), with later versions adopting more scalable file systems to improve reliability and performance on large datasets.

With the decline of SGI’s hardware business and a shift toward Linux-based solutions, official development and support for IRIX waned, and the operating system was discontinued in the mid-2000s. IRIX left a lasting impact on computer graphics, contributing to OpenGL, high-performance visualization workflows, and RenderMan pipelines used in film and media production.