Design
Component Library
Plain-language definitionA maintained collection of reusable interface patterns with documented behavior and states. It turns repeated solutions into shared product infrastructure.
Why it matters
Use the term to make a better decision.
In practice, component library matters when a team needs to connect a technical or creative choice to a visible change in clarity, performance, discovery, or conversion. The useful question is not whether the term sounds sophisticated. It is what decision it helps the team make.