JS. Intermediate JavaScript Questions Breakdown to Crack Any Interview:

 Level        Type

Intermediate              Arrays, objects, DOM, events, ES6 features, scope, closures



1. What is the DOM?
➤ DOM stands for Document Object Model – it represents the structure of an HTML page using objects.

2. What is event bubbling?
➤ When an event starts from the innermost element and bubbles up to its parents.

3. What are array methods like map(), filter()?
➤ map() transforms elements, filter() returns elements that match a condition.

4. How do you handle events in JavaScript?
➤ Using addEventListener():

button.addEventListener("click", () => alert("Clicked!"));

5. What is this in JavaScript?
➤ this refers to the object that is currently calling the function.

6. What is a closure?
➤ A closure is when a function remembers its lexical scope even after it is executed outside that scope.

7.How do you manipulate classes in DOM?
➤ Using classList.add(), remove(), toggle().

8. What is destructuring?
➤ Extracting values from objects or arrays:

const {name, age} = person;


9. What are default parameters?
➤ You can assign a default value to a function parameter:

function greet(name = "Guest") { ... }

10. Difference between synchronous and asynchronous code?
    ➤ Synchronous: runs line-by-line.
    ➤ Asynchronous: does not wait (like API calls, setTimeout).






















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