Ron Mace from the Institute of Human-Centered Design defined Universal Design as "the design of products and environments to be usable by all people, to the greatest extent possible, without the need for adaption or specialized design". This idea was applied specifically to learning by an organization called CAST in the 1990s. CAST defines Universal Design for Learning this way: "Universal design for learning is a framework to improve and optimize teaching and learning for all people based on scientific insights into how humans learn."
Universal Design for Learning (UDL) isn't equivalent to accommodations. Both are related to accessibility, but one is reactive while the other is proactive. An accommodation is a supportive
service provided to help students access education. This may look like giving a student extended time on an exam or printing out a copy of the course presentation.
However, UDL doesn't focus on making accommodations for an
individual student. UDL is a way of designing instruction so that the least amount of accommodations are needed and the content is accessible to everyone.
The image below does an excellent job illustrating the difference between UDL and learner accommodations. In the picture, we can see that equality doesn't always mean that each student is set up for success. Equity is solved through accommodations which can sometimes make students feel singled out. Accessibility removes barriers so that accommodations are not needed.
Can't see this image? Listen to a description.