feature of Org mode that handles source code for multiple languages. It can execute source code from within Org mode documents, making it convenient for producing literate programming documents and managing reproducible research. Note that Org-babel is now incorporated into Org-mode as 'working with source code' and no longer a separate extension.
Babel: active code in Org-mode
How to Use Emacs Org-Babel Mode to Write Literate Programming Document in R Language