JavaScript Interview - Intermediate Level
For developers with 2-4 years of JavaScript experience. Master closures, prototypes, async programming, ES6+ features, and functional programming patterns.
25-30 minutes
2-4 years of JavaScript experience
Who is this for?
Mid-level JavaScript developers
Frontend developers with experience
Developers preparing for mid-senior roles
Engineers building complex web applications
What you'll practice
Understanding closures deeply
Working with prototypes
Mastering async/await
Using ES6+ features effectively
Applying functional programming
Understanding the event loop
Topics covered
Advanced Concepts
Closures and lexical scope
Prototypes and prototype chain
this keyword
Hoisting
Async Programming
Promises
Async/await
Error handling
Event loop basics
ES6+
Arrow functions
Destructuring
Spread/Rest operators
Template literals
Modules
Functional Programming
Higher-order functions
map, filter, reduce
Pure functions
Immutability
Example questions
Q:
Can you explain what a closure is and provide a practical example?
Q:
How does the prototype chain work in JavaScript?
Q:
What is the difference between Promises and async/await?
Q:
How does the "this" keyword work in different contexts?
Q:
What are arrow functions and how do they differ from regular functions?
Q:
Can you explain the event loop and how JavaScript handles concurrency?
Preparation tips
Study closures until you truly understand them
Practice with Promises and async/await
Learn about prototypal inheritance
Master ES6+ features
Practice functional programming with arrays
Understand how "this" works in different scenarios
Continue your journey
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