CERNLIB

CERNLIB, or the CERN Program Library, is a large collection of software libraries for high-energy physics computing, originally developed at CERN and widely used through the 1980s and 1990s. It provides a broad set of Fortran- and C-callable routines for numerical computation, data input and output, event simulation, geometry, and physics analysis. The library was designed to run on multiple platforms, including UNIX variants and VMS, to support large-scale, multi-experiment software bases.

Major components of CERNLIB include HBOOK and HIGZ for histogramming and graphics; PAW (Physics Analysis Workstation) for interactive data analysis; ZEBRA for persistent data I/O and data structures; and a collection of utilities for random-number generation, geometry, particle identification, and Monte Carlo event generation. Together, these tools offered a portable foundation and common interfaces that dominated many high-energy physics workflows for decades.

In the late 1990s and early 2000s, CERNLIB began to be eclipsed by newer software ecosystems, most notably ROOT, a modern data-analysis framework developed at CERN. Development of CERNLIB slowed and eventually ceased, though the library remained in use for legacy code and documentation for some time. Today CERNLIB is of historical importance in computational high-energy physics; several components have seen continued maintenance by dedicated communities, while most new projects have migrated to ROOT and other contemporary tools.