What does it mean for a learning resource to be "open"? The 5R framework, proposed by David Wiley, defines the major characteristics of "open" content.

Retain
the right to make, own, and control copies of the content

Reuse
the right to use the content in a wide range of ways (e.g., in a class, in a study group, on a website, in a video)

Revise
the right to adapt, adjust, modify, or alter the content itself (e.g., translate the content into another language)

Remix
the right to combine the original or revised content with other open content to create something new (e.g., incorporate the content into a mashup)

Redistribute
the right to share copies of the original content, your revisions, or your remixes with others (e.g., give a copy of the content to a friend) 

This material was created by David Wiley and published freely under a Creative Commons Attribution 4.0 license at: http://opencontent.org/blog/archives/3221