The R environment is a powerful software suite that started as a model for the S language originally developed at Bell Laboratories. The original code base was created by Ross Ihaka and Robert Gentleman in 1993. It rapidly grew with the help of others, and it has since become a standard in statistical computing. The software suite itself has grown well beyond an implementation of a language and has become an "environment". It is extensible, and the wide variety of packages that are available help make it a powerful resource that continues to grow in popularity and power.

Our aim in this book is to provide a resource for programming using the R language, and we assume that you will be making use of the R environment to implement and test your code. The book can be roughly divided into four parts. In the first part, we provide a discussion of the basic ideas and topics necessary to understand how R classifies data and the options that can be used to make calculations from data. In the second part, we provide a discussion of how R organizes data and the options available to keep track of data, display data, and read and save data. In the third part, we provide a discussion on programming topics specific to the R language and the options available for object-oriented programming. In the fourth part, we provide several extended examples as a way to demonstrate how all of the topics can fit together to solve problems.