JavaScript Preparation Pack

Deep dive into prototype chains, closures, scopes, asynchronous event cycles, execution contexts, and core engine performance.

Question Cards

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Frequently Asked Questions

Is JavaScript multithreaded?

No, JavaScript is a single-threaded language, but browser web APIs run asynchronous operations in helper threads.

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JavaScript Preparation Pack

Question Cards

What are JavaScript Closures and how are they useful in practice?

Explain event delegation in JavaScript and why we should use it.

1 . What is the difference between let, const, and var?

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

What are closures in JavaScript?

Explain Event Delegation in JavaScript.

What is the Event Loop in JavaScript?

What is the difference between map(), filter(), and reduce()?

Explain the difference between call(), apply(), and bind().

What is Prototypal Inheritance in JavaScript?

How would you optimize a JavaScript application with performance issues?

What is hoisting in JavaScript?

What is the Temporal Dead Zone (TDZ)?

What are template literals in JavaScript?

What is destructuring in JavaScript?

What is the spread operator (...) in JavaScript?

What is the rest parameter in JavaScript?

What is the difference between null and undefined?

What are arrow functions in JavaScript?

What is the difference between function declarations and function expressions?

What are JavaScript data types?

What is a Promise in JavaScript?

What is async/await in JavaScript?

What is the difference between synchronous and asynchronous code?

What are higher-order functions in JavaScript?

What is currying in JavaScript?

What is debouncing in JavaScript?

What is throttling in JavaScript?

What is localStorage and sessionStorage?

What is JSON and how is it used in JavaScript?

What is the difference between shallow copy and deep copy?

What is a callback function?

What is memoization in JavaScript?

What is a generator function?

What are WeakMap and WeakSet?

What is currying versus partial application?

What is the JavaScript execution context?

What is the difference between microtasks and macrotasks?

What are modules in JavaScript?

How does garbage collection work in JavaScript?

What is the Proxy object in JavaScript?