In Angular, `NgZone` is a service provided by the Angular framework that helps manage and control the execution of asynchronous tasks and change detection. It is responsible for triggering change detection and updating the view when changes occur. The primary purpose of `NgZone` is to handle and optimize the execution of code that runs outside of Angular's zone, such as events from third-party libraries or asynchronous operations like timers, AJAX requests, or WebSockets. By default, Angular runs in a zone called the "Angular zone." When code executes within this zone, Angular's change detection mechanism is triggered automatically, and the view is updated accordingly. However, when code runs outside of the Angular zone, Angular may not be aware of the changes, leading to potential issues with the application state and view synchronization. `NgZone` provides a way to explicitly run code inside or outside of the Angular zone. It offers two methods for executing code: `run()` and `runOutsideAngular()`. 1. `run()`: The `run()` method executes the provided function inside the Angular zone. This ensures that any changes triggered by the function will be detected and updated in the view. 

   import { Component, NgZone } from '@angular/core';

   @Component({
     selector: 'app-example',
     template: `
       <button (click)="onClick()">Run Code Inside NgZone</button>
     `,
   })
   export class ExampleComponent {
     constructor(private ngZone: NgZone) {}

     onClick() {
       this.ngZone.run(() => {
         // Code executed inside NgZone
         // Angular change detection is triggered
       });
     }
   }
In the above example, the `onClick()` method is wrapped inside the `run()` method of `NgZone`. When the button is clicked, the code inside the `run()` function is executed within the Angular zone, ensuring that any changes made are detected and updated in the view. 2. `runOutsideAngular()`: The `runOutsideAngular()` method allows you to execute code outside of the Angular zone. This is useful for running code that doesn't require Angular's change detection or when optimizing performance for tasks that don't affect the UI. 

   import { Component, NgZone } from '@angular/core';

   @Component({
     selector: 'app-example',
     template: `
       <button (click)="onClick()">Run Code Outside NgZone</button>
     `,
   })
   export class ExampleComponent {
     constructor(private ngZone: NgZone) {}

     onClick() {
       this.ngZone.runOutsideAngular(() => {
         // Code executed outside NgZone
         // Angular change detection is not triggered
       });
     }
   }
In the above example, the `onClick()` method runs the code inside the `runOutsideAngular()` method. This ensures that the code is executed outside of the Angular zone, preventing unnecessary change detection and view updates. Conclusion : Using `NgZone`, you can control and optimize the execution of code inside and outside the Angular zone, ensuring efficient change detection and synchronization between the application state and the view.