React's useState Hook: How It Stores and Updates Component Data

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The useState Hook in React is used to keep and modify data inside a component. Its basic syntax pairs a current value with a setter function, declared as a state variable and an update function. A counter example shows it starting at zero and being raised, lowered, or reset through the setter. Each state change prompts React to refresh the user interface so it reflects the new data. The article walks through this pattern as a foundational building block for interactive React components.

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