Angular MCQ Quiz.

Angular is a TypeScript-based front-end framework developed by Google for building single-page web applications (SPA) using components.

TypeScript is a superset of JavaScript that adds: Static typing, Interfaces, Classes, and better tooling support. Angular is built using TypeScript.

A component controls a part of the UI. Each Angular app is made of components.

A module groups components, services, pipes, and directives into cohesive blocks of functionality.

Data binding connects HTML and TypeScript. Types include: Interpolation {{name}}, Property Binding [src], Event Binding (click), and Two-way Binding [(ngModel)].

Directives modify DOM behavior. Examples include structural directives like *ngIf and *ngFor, and attribute directives like ngClass.

Dependency Injection is a pattern where Angular automatically provides instances of services to components upon request (usually in the constructor).

A service contains reusable business logic, API calls, and shared data that can be used across multiple components.

Routing allows navigation between different views or pages in a single-page application without a full browser refresh.

Lazy loading allows you to load feature modules only when the user navigates to them, which improves initial load time and performance.

An Observable is used for handling asynchronous data streams using RxJS. It is commonly used for HTTP requests, events, and forms.

Promises handle a single value and cannot be cancelled. Observables handle multiple values over time and can be unsubscribed from (cancelled).

Pipes are simple functions used in templates to transform and format data (e.g., uppercase, date, currency).

Template forms use the HTML template for logic; Reactive forms use TypeScript code to define the form structure, making them more scalable and testable.

Change detection is the mechanism by which Angular updates the DOM when component data changes. Strategies include Default and OnPush.

OnPush tells Angular to only check a component for changes when its Inputs change, an event fires inside it, or an Observable emits. It's used for performance optimization.

Hooks like ngOnInit, ngOnChanges, ngAfterViewInit, and ngOnDestroy allow you to tap into key moments of a component's life.

@ViewChild is a decorator used to access a child component, directive, or a DOM element directly from the parent component class.

TrackBy is used to improve performance in lists by telling Angular how to uniquely identify items, avoiding unnecessary full DOM re-renders.

HTTP Interceptors allow you to intercept and modify HTTP requests and responses globally (e.g., for adding auth tokens or handling errors).

Angular's architecture is modular and component-based, relying on Templates, Metadata, Services, Dependency Injection, and Routing to build scalable apps.

Subject has no initial value. BehaviorSubject stores and emits the latest value to new subscribers. ReplaySubject stores multiple previous values.

Zone.js is a library that Angular uses to track asynchronous operations and trigger change detection automatically when they complete.

Use Lazy Loading, OnPush change detection, TrackBy for lists, AOT compilation, Tree shaking, and properly manage subscriptions.

Ahead-of-Time compilation compiles the application during the build phase, leading to faster loads, smaller bundles, and better security.

State management can be handled via built-in Services + RxJS, modern Signals, or dedicated libraries like NgRx for large-scale global state.

Signals are a modern reactivity primitive for managing state that provides fine-grained updates to the DOM without relying on Zone.js.

Angular uses a hierarchical system of injectors (Root, Module, Component) to provide scoped services and maintain the singleton pattern where appropriate.

Server-Side Rendering (Angular Universal) renders the initial page on the server for better SEO and faster first contentful paint.

Introduced in modern Angular, standalone components allow you to build components without the need for traditional NgModules.