R is a software package and programming language widely used for data analysis by researchers in the social sciences, natural sciences, and humanities. The materials offered in this resource provide instruction on using R for spatial data analysis and modeling. Readers who are unfamiliar with R should not fear, because the materials begin with an introduction to using R that covers everything from the installation and basic data types, to generating complex graphics like scatter plots. Once users are comfortable with R programming, they can move on to the spatial analysis instructions, which guide users through the basics of spatial data, remote sensing image analysis, and MODIS data. The site is easy to navigate by clicking the "Next" and "Previous" buttons to move through the materials in order. Each section of the instructions offers an introduction to the concept covered, programming language to apply and practice, and links to other materials for further reference. This resource was created by Robert J. Hijmans, a researcher at the University of California-Davis.