ui-design means User interface design. It is the design of websites, computers, appliances, machines, mobile communication devices, and software applications with the focus on the user's experience and interaction.

- Stackoverflow.com Wiki
2 articles, 3 books. Go to books ↓

"The 10 most general principles for interaction design. They are called 'heuristics' because they are more in the nature of rules of thumb than specific usability guidelines."

If you have considered creating one for your product or company, are in the process of making one, or have tried and given up, hopefully these insights will help you create a better design system for your company.