CRAN

CRAN, the Comprehensive R Archive Network, is a distributed network of servers that host the R software, its packages, and related documentation. It serves as the primary repository for installing and distributing user-contributed extensions for the R programming language, enabling users to install packages with a single command.

CRAN is managed by the R Foundation for Statistical Computing and maintained by a global community of volunteer package developers and mirror operators. The network comprises multiple mirrors around the world to provide fast downloads and redundancy. CRAN hosts packages in a standardized format, each package containing R code and optional compiled code, along with metadata, manuals, and vignettes. It also provides binaries for supported operating systems, notably Windows and macOS, in addition to source packages.

New or updated packages are submitted to CRAN by authors. Submissions are reviewed by CRAN maintainers who run automated checks across platforms using R CMD check and other validation steps. Packages must comply with CRAN policies on licensing, code quality, and compatibility with dependencies; issues identified during checks must be resolved before acceptance. Once approved, the package is added to the repository and becomes available to users through install.packages() and the R package manager. Older versions may remain accessible, and the repository maintains version history.

CRAN also hosts CRAN Task Views, which curate packages for specific topics, and provides documentation and user guides. As a central component of the R ecosystem, CRAN supports reproducible research by offering a stable, centralized distribution mechanism for R software and its extensions.