Interview Preparation

What is the difference between == and === in JavaScript?

What is a closure in JavaScript?

Explain event delegation in JavaScript.

What is the difference between Promises and async/await?

Explain the JavaScript event loop.

What is hoisting in JavaScript?

What is the Virtual DOM in React?

How does useEffect cleanup work?

When would you use useCallback vs useMemo?

How does React reconciliation work?

Explain the CSS Box Model.

What is the difference between Flexbox and CSS Grid?

What is the difference between position relative, absolute, fixed, and sticky?

What is the time complexity of common array operations?

What is the difference between BFS and DFS?

What is Dynamic Programming? When do you use it?

Explain Dijkstra's algorithm.

What is horizontal vs vertical scaling?

How would you design a URL shortener like bit.ly?

What is CAP theorem?

What is the difference between SQL and NoSQL?

What is a database index and how does it work?

Explain the difference between INNER, LEFT, RIGHT, and FULL OUTER JOIN.

What is the difference between a list and a tuple in Python?

What are Python decorators?

Tell me about yourself.

Tell me about a time you overcame a challenge.