Suggest an editImprove this articleRefine the answer for “What is shared state?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**Shared state** is state that is shared between multiple components, where a change in one place must be reflected in another. **Key point:** shared state is a single point of truth for multiple participants: change it in one place, and it changes everywhere.Shown above the full answer for quick recall.Answer (EN)Image**Shared state** is common state that is **shared between multiple components**. --- ### What this means: When two or more components **use the same data**, and a change in one place must be reflected in another. For example: - The cart on the product page and the icon in the header - An authentication flag in the navbar and in the profile - A shared filter that affects multiple lists --- ### Where shared state lives: - In a **service** (most often) - In an **RxJS stream** (`BehaviorSubject`, `signal`) - In a **store** (NgRx, NGXS, and so on) --- ### Why it matters: Without shared state, components easily "drift apart": one shows stale data, another shows fresh data. Shared state guarantees that **every part of the application "looks at the same place"**. --- **Conclusion:** Shared state is like **a single point of truth for multiple participants**. Change it in one place, and it changes everywhere.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.