JavaScript Interview Guide (Beginner to Intermediate)

⚡ JavaScript Interview Guide (Beginner to Intermediate)

Hello everyone 👋
Welcome back!

Preparing for web development interviews? This JavaScript Interview Guide will help you understand important concepts with simple explanations 🚀

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🌟 Why Learn JavaScript?

- Used in web development 🌐
- High demand in jobs 📈
- Works in browser & backend (Node.js)

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🧠 BASIC QUESTIONS

1. What is JavaScript?

JavaScript is a scripting language used to create dynamic web pages.

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2. Difference between var, let, const?

- var → function scoped
- let → block scoped
- const → block scoped (constant)

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3. What is a variable?

A container to store data.

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4. What are data types?

String, Number, Boolean, Object, Undefined, Null

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5. What is a function?

Reusable block of code.

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6. What is a loop?

Used to repeat tasks (for, while)

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7. What is an array?

Collection of values.

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8. What is an object?

Collection of key-value pairs.

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9. What is DOM?

Document Object Model (used to manipulate HTML)

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10. What is an event?

Action like click, scroll, input.

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⚡ INTERMEDIATE QUESTIONS

11. What is hoisting?

Variables and functions are moved to top during execution.

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12. What is closure?

Function with access to outer scope.

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13. What is callback function?

Function passed as argument.

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14. What is promise?

Handles asynchronous operations.

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15. What is async/await?

Simplifies working with promises.

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16. Difference between == and ===?

== → value compare
=== → value + type compare

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17. What is scope?

Area where variable is accessible.

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18. What is event bubbling?

Event flows from child to parent.

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19. What is arrow function?

Short syntax for functions.

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20. What is JSON?

Format to store and exchange data.

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⭐ Tips for Interview

- Practice coding
- Understand concepts deeply
- Build small projects

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📌 Conclusion

This was a complete JavaScript interview guide.
Prepare well to crack interviews and improve your skills 🚀

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📢 Also Read

- Python Interview Questions
- C++ Interview Questions
- JavaScript Programs

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