Thousand, J. & Villa, R. (2017, December 14). Applying the Four Elements of UDL to Lesson Design.

As a generic concept, universal design refers to the creation and design of products and environments such that they can be used without being modified. Curb cuts are an example of universal design: they are expensive to add after the fact but cost virtually nothing if designed in from the start, and they offer many benefits (easier wheelchair and stroller access to sidewalks, less joint stress for joggers).