Data Flow and Component Communication
Explore the core principles of React data flow and component communication. Understand how to lift state up to a common ancestor and use functions as props to maintain a single source of truth and achieve predictable, synchronized UI updates across components.
As our applications grow, components rarely exist in isolation. They need to share data, respond to each other, and stay in sync. React enforces a clear direction for this interaction: data flows down, and events flow up. Once we internalize this pattern, component communication becomes predictable instead of confusing.
Why sharing state between components is challenging
When two components need access to the same piece of data, a natural question arises. Where should that data live? If each component keeps its own copy, they can easily fall out of sync. If one updates and the other does not, the UI becomes inconsistent. The root cause is a duplicated state. When the ...