Quartz: What’s the best way to learn the programming language R? (Preferably, for free)

Quartz: What’s the best way to learn the programming language R? (Preferably, for free). “As data becomes an ever larger part of work, for many people spreadsheets just are not enough. Programs like Microsoft Excel and Google Sheets are powerful tools, but they have limitations in terms of the amount of data you can work with, the kind of analyses you can do, and the types of charts you can make. When data users reach these limitations, the obvious next step is learning a programming language.”