Error "No provider for HttpClient" in Angular: causes and fix

Hello everyone! I'm a beginner in Angular and TypeScript. I'm creating a simple application that should receive data from a server via HTTP. I generated a service using Angular CLI and added HttpClient to it. But when I run the application, the following error appears in the browser console: ``` NullInjectorError: No provider for HttpClient! ``` My service looks like this (`data.service.ts` file): ```typescript import { Injectable } from '@angular/core'; import { HttpClient } from '@angular/common/http'; @Injectable({ providedIn: 'root' }) export class DataService { constructor(private http: HttpClient) { } getUsers() { return this.http.get('https://jsonplaceholder.typicode.com/users'); } } ``` And the component that uses the service (`app.component.ts` file):