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docs/en/Community-Articles/2024-09-24-Angular-Difference-Btw-Promise-Observable/post.md

@@ -1,6 +1,6 @@
 # Difference Between "Promise" and "Observable" in Angular
 
-`Promises` and `Observables` are both used in TypeScript for handling asynchronous operations, but they have different use cases and behaviors. I will clearly summarize the key characteristics differences between `Promises` and `Observables` ...
+In this article, I will mention the differences between `Promise` and `Observable` . They are used in TypeScript (Angular) for handling async operations but have different use cases and behaviors. Let's see these six differences...
 
 ![Cover](cover.png)
 
@@ -8,66 +8,79 @@
 
 ## 1. Eager or Lazy Evaluation
 
-- **Promise**: A `promise` is **eager**! This means that as soon as a  `promise` is created, it executes the operation like initiating immediately an HTTP request. **You can't control the execution start time; it begins right away!**
-- **Observable:** An `observable` is a **lazy** operation! It doesn't start executing until you subscribe to it. This allows you to define an `observable` without triggering the actual operation until it's needed.
+- **Promise**: A `promise` is **eager**! This means that as soon as a  `promise` is created, it executes the operation, like initiating immediately an HTTP request. **You can't control the execution start time; it begins right away!**
 
+- **Observable:** An `observable` is a **lazy** operation! It doesn't start executing until you subscribe to it. This allows you to define an `observable` without triggering the actual operation until it's needed.
 
+  
 
-## 2. Handling Single or Multiple Values
+## 2. Handling Value Count
 
 - **Promise:** A `promise` is designed to **handle a single async value**. Once the operation completes, it either resolves with a value or rejects with an error, and that's it! You can't emit multiple values with a single `promise`.
-- **Observable:** An `observable` **can emit multiple values** over time. It can several values and it can continue to do so until it either completes or errors out. So `observable` is ideal for event streams or data streams.
 
+- **Observable:** An `observable` **can emit multiple values** over time. It can have several values, and it can continue to do so until it either completes or errors out. So `observable` is ideal for event streams or data streams.
 
+  
 
-## 3. Cancel or Forget
+## 3. Cancellablity
 
-- **Promise:** Once a `promise` is created and the **operation has started, you cannot cancel it**. The `promise` will resolve or reject eventually, but there's no way to stop it from executing.
-- **Observable:** An `observable` **can be canceled**. If you unsubscribe from an `observable`, it stops emitting values and can clean up any resources like cancelling an ongoing HTTP request. This makes `observable` more flexible in scenarios where you need to abort an operation, especially to cancel for long lasting HTTP requests.
+- **Promise:** Once a `promise` is created and the operation has started**, you cannot cancel it!** The `promise` will resolve or reject eventually, and   there's no way to stop it from being executed.
 
+- **Observable:** An `observable` **can be canceled**. If you unsubscribe from an `observable`, it stops emitting values and can clean up any resources like canceling an ongoing HTTP request. This makes `observable` more flexible in scenarios where you need to abort an operation.
 
+  
 
 ## 4. Chaining and Composition
 
 - **Promise:** It **supports chaining** using `.then()` for handling the result and `.catch()` for handling errors. This is straightforward but can become complex for more advanced scenarios.
-- **Observable:** It **supports powerful operators** like `map`, `filter`, `merge`, `switchMap`. This allows for complex composition and transformation of data streams and makes suitable for handling complex async scenarios.
 
+- **Observable:** It **supports powerful operators** like `map`, `filter`, `merge`, `switchMap`. This allows for complex composition and transformation of data streams and makes it suitable for handling complex async scenarios.
 
+  
 
 ## 5. Error Handling:
 
 - **Promise:** Error handling in `promise` is done usually using `.catch()`. However, **if an error occurs**, the `promise` will reject, and **the chain will stop**.
-- **Observable:** It has more **robust error handling mechanisms**. You can handle errors using operators like `catchError` and decide whether to recover, continue or retry the process. It can also complete successfully after an error is handled.
 
+- **Observable:** It has more **robust error-handling mechanisms**. You can handle errors using operators like `catchError` and decide whether to recover, continue or retry the process. It can also be completed successfully after an error is handled.
 
+  
 
 ## 6. Built-In or RxJS
 
-- **Promise:** It's a **built-in feature of JavaScript** and a part of the ECMAScript. Almost all **browsers support it**.
-- **Observable:** It's **not a built-in feature of JavaScript**. In Angular, they are typically provided by the `RxJS` library.
+- **Promise:** It’s a **built-in feature of JavaScript** and a part of the ECMAScript. Almost all **browsers support it**.
+- **Observable:** It’s **not a built-in feature of JavaScript**. In Angular, it’s provided by the `RxJS` library.
 
 
 
-## 7. Use Cases
+---
+
+
+
+## Use Cases
+
+**Promise:**
+
+- Simple async operations that return a single result, like fetching data from a Web API.
+- Scenarios where you don’t need to cancel the operation.
+- Handling a single event or action.
+
+**Observable:**
+
+- Operations that might emit multiple values over time, such as `WebSocket` connections, user input events, or real-time data streams.
+- When you need the ability to cancel the operation.
+- Complex async flows require composition, transformation, or error handling.
+
+
+
+---
 
-- **Promise:**
-  - Simple async operations that return a single result, like fetching data from a Web API.
-  - Scenarios where you don't need to cancel the operation.
-  - Handling a single event or action.
 
-- **Observable:**
-  
-  - Operations that might emit multiple values over time, such as `WebSocket` connections, user input events, or real-time data streams.
-  
-  - When you need the ability to cancel the operation.
-  
-  - Complex async flows requiring composition, transformation, or error handling.
-  
-    
 
 ## Examples
 
 ### Promise Example
+
 ```javascript
 const myPromise = new Promise((resolve, reject) => {
   setTimeout(() => {
@@ -78,8 +91,6 @@ const myPromise = new Promise((resolve, reject) => {
 myPromise.then(value => console.log(value)).catch(error => console.error(error));
 ```
 
-
-
 ### Observable Example
 
 ```typescript
@@ -107,7 +118,7 @@ const subscription = myObservable.subscribe({
 
 
 
-### Summary:
+## Summary
 
-- **Promise** is simple and suitable for operations that return a single value or need to handle a single event. It's eager and can't be canceled.
-- **Observable** is more flexible, especially for handling multiple values over time, allowing for complex data manipulation, and providing the ability to cancel operations. It supports lazy operations via `RxJS`.
+- **A promise** is simple and suitable for operations that return a single value or need to handle a single event. It’s eager and can’t be canceled.
+- **An observable** is more flexible, especially for handling multiple values over time, allowing for complex data manipulation, and providing the ability to cancel operations. It supports lazy operations via `RxJS`.