The Rcpp package simplifies the integration of C++ code with R by providing a consistent C++ class hierarchy that maps various R objects (vectors, matrices, functions, environments, etc.) to dedicated C++ classes. This allows for seamless data interchange between R and C++, managed by simple, flexible, and extensible concepts. C++ code can be compiled, linked, and loaded on-the-fly, or added via packages. The package supports error and exception handling, making it easier for programmers to combine C++ code with R. Key design choices include lightweight encapsulation of R objects in C++ classes, automatic garbage collection, code inlining, and data interchange functions like `wrap` and `as`. The article highlights the benefits of using Rcpp over traditional R APIs through examples and discusses related work, including other packages and approaches for integrating C++ and R. It also covers the history of Rcpp, its use cases, and ongoing development efforts, such as 'Rcpp sugar' and 'Rcpp modules'.The Rcpp package simplifies the integration of C++ code with R by providing a consistent C++ class hierarchy that maps various R objects (vectors, matrices, functions, environments, etc.) to dedicated C++ classes. This allows for seamless data interchange between R and C++, managed by simple, flexible, and extensible concepts. C++ code can be compiled, linked, and loaded on-the-fly, or added via packages. The package supports error and exception handling, making it easier for programmers to combine C++ code with R. Key design choices include lightweight encapsulation of R objects in C++ classes, automatic garbage collection, code inlining, and data interchange functions like `wrap` and `as`. The article highlights the benefits of using Rcpp over traditional R APIs through examples and discusses related work, including other packages and approaches for integrating C++ and R. It also covers the history of Rcpp, its use cases, and ongoing development efforts, such as 'Rcpp sugar' and 'Rcpp modules'.