Top 50 Angular Interview Questions You Must Know!

Here are some essential Angular interview questions to help you prepare:

1. What is the main purpose of Angular?
2. What are directives in Angular and how many types of directives exist?
3. Explain data bindings and the different types.
4. What are the basic components involved in Angular?
5. What’s the difference between AngularJS and Angular?
6. What are components and modules in Angular?
7. What are decorators in Angular?
8. What is metadata or annotations in Angular?
9. What are templates in Angular?
10. What is SPA and how do you implement it in Angular?
11. Explain the importance of routing in Angular & how to implement it.
12. What is lazy loading in Angular?
13. How do you implement lazy loading in Angular?
14. What is Node.js?
15. What is NPM?
16. Why is the node_modules folder important?
17. What is package.json?
18. What is TypeScript?
19. What is the need for Angular CLI?
20. What are services in Angular?
21. When would you use content projection?
22. Explain content projection slots in Angular.
23. Why do we need ViewChild and ViewChildren in Angular?
24. What is a template reference variable?
25. Explain ContentChild and ContentChildren.
26. Differentiate between ViewChild, ViewChildren, ContentChild, and ContentChildren.
27. What is { static: true } in ViewChild?
28. What is the importance of Angular component hooks/life cycles?
29. Explain Angular life cycle hooks in detail.
30. Differentiate between constructor and ngOnInit().
31. How do you implement lazy loading in Angular?
32. How do you implement HTTP in Angular?
33. How do you pass data between components?
34. What are pipes in Angular?
35. Can you give examples of inbuilt Angular pipes?
36. How do you write a custom pipe?
37. What is RxJs and why is it needed?
38. What are observables and observers?
39. What is a stream in RxJs?
40. What is the use of subscribe in RxJs?
41. How do you unsubscribe from a stream?
42. What are operators in RxJs?
43. Where have you used RxJs in Angular?
44. Differentiate between RxJs and Promises.
45. How do you install RxJs?
46. Why is RxJs called push/reactive and not pull/imperative?
47. Name some RxJs operators.
48. What are interceptors in Angular?
49. How do you implement interceptors?
50. What are some uses of interceptors, and can we provide multi-interceptors?

Just an answer from today:

Hi!

Thanks for your message.

Regarding the salary range - only our Hiring Manager is responsible for that negotiations after performance evaluation in the end of the recruitment process. How I can support here is - if you could share with me your range - I can quickly check if it´s among the budget for the role.

Best regards,

‼️ 𝕬𝖓𝖌𝖚𝖑𝖆𝖗 𝕽𝖊𝖑𝖊𝖆𝖘𝖊 - v19.2.12

Contain diverse fixes:

- cancel reader when app is destroyed
- prevent reading chunks if app is destroyed
- avoid conflicts between HMR code and local symbols
- cleanup rxResource abort listener
- unregister onDestroy in toSignal
- etc...

Link

#angular #angularRelease #angular19 #ng19

———
@angularMunich

‼️ Happy BDay Java! 🫶🏻❤️🔥

———
@angularMunich

‼️ 𝕬𝖓𝖌𝖚𝖑𝖆𝖗 v20 ‼️

DevTools will introduce support for deferrable views and incremental hydration 🔥

Thanks to Matthieu for the slick feature!

#angular #angular20 #typenoscript #webdev #webdevelopment #webperformance #javanoscript

‼️ 𝕬𝖓𝖌𝖚𝖑𝖆𝖗 𝕽𝖊𝖑𝖊𝖆𝖘𝖊 v19.2.13 ‼️

Contain diverse fixes:

common
- avoid injecting ApplicationRef in FetchBackend

service-worker
- do not register service worker if app is destroyed before it is ready to register

Link

#angular #angularRelease #angular19 #ng19

———
@angularMunich

https://github.com/ng-select/ng-select/releases/tag/v15.0.0


FYI!

‼️ Happy Father's day and Happy NG-Day!

Let's upgrade to ng20!!!!!!!

https://github.com/angular/angular/releases/tag/20.0.0

⚒️ Async & Sync Cheat Sheet Angular 🛠

👉 No reactivity + non-reactive DOM
- afterNextRender()

👉 No reactivity + plain read
- signal()

👉 Streams
- RxJS Observable

👉 Signals, sync derivation:
- Writable: signal()
For local, mutable state

- Read-only: computed()
For derived, read-only state

- Writable derived: linkedSignal()
Derived signal that is also writable

👉 Signals, async derivation
- Promise: resource()
For async operations returning a Promise
( only GET )

- Observable: rxResource()
For async data from an Observable
( only GET )

- HttpClient: httpResource()
( only GET )

Mutations to handle
POST, PATCH, PUT, DELETE
are missing for now

👉 Side Effects on sync APIs
- afterRenderEffect()
Runs an effect after app rendered

- effect()
Runs before component sync

#angular #signals

‼️ 𝕬𝖓𝖌𝖚𝖑𝖆𝖗 𝕽𝖊𝖑𝖊𝖆𝖘𝖊 v20.0.1 ‼️

Contain diverse fixes which improve performance and migrations

Link

#angular #angularRelease #angular20 #ng20

———
@angularMunich

RFC - Angular official mascot #61733

https://github.com/angular/angular/discussions/61733

I'm so sorry... but it's funny 😂 😂 😂 😂

🚀 Angular 20 just dropped a MASSIVE performance upgrade!

The new @angular/build package is replacing @angular-devkit/build-angular and the results are incredible:
📦 60% smaller installs (~115 MB vs ~291 MB)
⚡️ 5x faster builds (esbuild vs Webpack)
🔥 4x faster dev server startup

What's changing?
✅ New projects: Get @angular/build by default
🔄 Existing projects: Keep working as-is (zero breaking changes)
🎯 Optional migration: Upgrade when you're ready

Old: @angular-devkit/build-angular:application
New: @angular/build:application

This is exactly what the Angular ecosystem needed—modern tooling that works faster without the Webpack overhead for most use cases.

#Angular #Angular20 #WebDev #JavaScript #TypeScript #Frontend #Performance