Frontend Interview Preperation Guide I created this repo to help engineers with their preparation for frontend interviews. Feel free to star/fork it for future reference.
Call for Help/Contribution Feel free to raise PRs to enrich this repo with more questions (Don't forget to add placeholder for answer as well). Also most of the answers are yet to be added. Feel free to add them as well.
What is CORS? How does it work in browsers? What is preflight request
Why do we need Redux? Why can't same thing be done by a global state?
Explain how does virtual DOM works exactly
What happens when you enter a URL in the browser?
Apart from the task queue, what other queues are there in browser?
If we define a class in JS using arrow functions and without using class keyword, would it work?
Describe ES6 features and properties.
How does virtual DOM works in React? Talk about React Fibre, the reconciliation algorithm of react.
What is event loop and how does it work? https://www.youtube.com/watch?v=cCOL7MC4Pl0
https://www.youtube.com/watch?v=8aGhZQkoFbQ
Difference between state and props
Why we need key in react lists? What happens if we provide the index as the key ?
How to improve performance of a web app
What are controlled and uncontrolled inputs in React ?
What is a closure? How can it be used ?
Why do we need redux? Why can't we just use a global state?
Event Propogation and Event bubbling?
Difference between debouncing and throttling?
Difference between call, apply and bind?
What is async and await. What does a async function return?
What is a Higher Order Component ? Give example and explain the use cases where it should be used.
How to deep clone a object in javascript ?
Implement a singleton class in Javascript.
Lifecycle hooks of react with use of each hook?
Does react component only update on state change or also on prop change ?
How to start a new Angular project from cli ?
Video tutorial links
Programming Questions