I’ve seen the five R’s used many times in reference to the OER space (Open Educational Resources). They include the ability to allow others to: Retain, Reuse, Revise, Remix and/or Redistribute content with the appropriate use of licenses. These are all some incredibly powerful building blocks, but I feel like one particularly important building block is missing–that of the ability to allow easy accretion of knowledge over time.
https://boffosocko.com/2018/08/30/the-sixth-r-of-open-educational-resources-oer/