A design system is a collection of reusable components, guided by clear standards, that can be assembled together to build any number of applications.
A design system isn’t only a collection of the assets and components you use to build a digital product. According to Emmet Connolly, director of product design at Intercom, “… most Design Systems are really just Pattern Libraries: a big box of UI Lego pieces that can be assembled in near-infinite ways. All the pieces may be consistent, but that doesn’t mean the assembled results will be. Your product is more than just a pile of reusable UI elements. It has structure and meaning. It’s not a generic web page, it’s the embodiment of a system of concepts.”
More simply put, the difference is in the standards and documentation that accompanies the assets. With a guide on why and how to use them, design components because easier to use and clearer to discern.
“Design systems are always evolving, and the way you share and encourage adoption of new iterations will evolve along the way as well.” –Diana Mounter, design systems manager at GitHub