Retrieved from CAST, http://www.cast.org
The framework of UDL is guided by three core principles: (1) provide multiple means for representing content, (2) provide multiple ways for learners to act and represent their knowledge, and (3) provide multiple ways for learners to engage with content. The image here illustrates these three principles in a color-coded fashion as well across representation (pink), action and expression (blue, and engagement (green). These each correspond to the neuroscience research that supports learning in three key areas of the brain.
Adapted from information provided on universal design for learning at CAST (http://www.cast.org) and the National Center on Universal Design for Learning (http://www.udlcenter.org)