Universal design is the process of creating products that are accessible to people with a wide range of abilities, disabilities, and other characteristics. Universally designed products accommodate individual preferences and abilities; communicate necessary information effectively (regardless of ambient conditions or the user's sensory abilities); and can be approached, reached, manipulated, and used regardless of the individual's body size, posture, or mobility. Application of universal design principles minimizes the need for assistive technology, results in products compatible with assistive technology, and makes products more usable by everyone, not just people with disabilities.
Typically, products are designed to be most suitable for the average user. In contrast, products that are designed according to principles of universal design are designed to be usable by everyone, to the greatest extent possible, without the need for adaptation or specialized design (Connell et al., The Principles of Universal Design ).
Universal design typically results in product features that benefit a variety of users, not just people with disabilities. For example, sidewalk curb cuts, designed to make sidewalks and streets accessible to those using wheelchairs, are today often used by kids on skateboards, parents with baby strollers, and delivery staff with rolling carts. Similarly, a door that automatically opens when someone approaches it is more accessible to everyone, including small children, workers whose arms are full, and people using walkers or wheelchairs.
At the Center for Universal Design  at North Carolina State University, a group of architects, product designers, engineers, and environmental design researchers established the following set of principles of universal design to provide guidance in the design of environments, communications, and products (Connell et al., 1997). They can be applied to academic environments, communications, and products.
- Equitable Use. The design is useful and marketable to people with diverse abilities. For example, a website that is designed so that it is accessible to everyone, including people who are blind, employs this principle.
- Flexibility in Use. The design accommodates a wide range of individual preferences and abilities. An example is a museum that allows a visitor to choose to read or listen to the description of the contents of a display case.
- Simple and Intuitive Use. Use of the design is easy to understand, regardless of the user's experience, knowledge, language skills, or current concentration level. Science lab equipment with control buttons that are clear and intuitive is a good example of an application of this principle.
- Perceptible Information. The design communicates necessary information effectively to the user, regardless of ambient conditions or the user's sensory abilities. An example of this principle being employed is when television programming projected in noisy public areas like academic conference exhibits includes captions.
- Tolerance for Error. The design minimizes hazards and the adverse consequences of accidental or unintended actions. An example of a product applying this principle is an educational software program that provides guidance when the user makes an inappropriate selection.
- Low Physical Effort. The design can be used efficiently and comfortably and with a minimum of fatigue. Doors that are easy to open by people with a wide variety of physical characteristics demonstrate the application of this principle.
- Size and Space for Approach and Use. Appropriate size and space is provided for approach, reach, manipulation, and use regardless of the user's body size, posture, or mobility. A flexible science lab work area designed for use by students with a wide variety of physical characteristics and abilities is an example of employing this principle.
For more information on universal design, explore The Center for Universal Design in Education . Additional examples of universal design can be found in the DO-IT publications Applications of Universal Design  and Universal Design of Instruction: Definition, Principles, and Examples . For more information about universal design as it applies to the web, consult the Knowledge Base article How does accessible web design benefit all web users? 
-  The Principles of Universal Design
-  Center for Universal Design
-  The Center for Universal Design in Education
-  Applications of Universal Design
-  Universal Design of Instruction: Definition, Principles, and Examples
-  How does accessible web design benefit all web users?