A reusable [React](/courses/reactjs) component solves a repeated UI or behavior problem without being unnecessarily tied to one page, dataset, or business scenario. Consider a component that is tightly coupled to article data: ```jsx function ArticleButton() { return ( ); } ``` If the visual button pattern is used elsewhere, a more reusable abstraction could be: ```jsx function Button({ children, onClick, variant = 'primary' }) { return ( ); } ``` Now it can support multiple contexts: ```jsx ``` ### Characteristics of Reusable Components A good reusable component generally has: ```text A focused responsibility Clear props Minimal assumptions about its parent Predictable behavior Composable structure Sensible defaults ``` ### Separate Data From Presentation When Useful Instead of letting every visual component perform its own API request: ```jsx function CourseCard() { // fetch course directly } ``` you can often pass the required data: ```jsx function CourseCard({ course }) { return

{course.title}

; } ``` This allows the same UI component to work with API data, cached data, test data, or locally generated data. ### Do Not Abstract Too Early Suppose two components happen to look similar today but have different responsibilities. Immediately combining them into one large configurable component can produce: ```text isArticle isCourse showAuthor showCategory compact horizontal specialMode ``` This often creates a component that is technically reusable but difficult to understand. Extract abstractions after a meaningful repeated pattern becomes clear. ### Interview-Ready Answer A reusable [React](/courses/reactjs) component has a focused responsibility, receives changing data or behavior through a clear props API, avoids unnecessary assumptions about where it is used, and composes cleanly with other components. Reusability should reduce duplication without creating overly generic components with excessive configuration.