Most common JavaScript interview questions
In this article, I will try to include some of the most common JavaScript interview questions with their answers.
1. What is JavaScript?
- JavaScript is a high-level, interpreted programming language used to create dynamic and interactive web pages and applications.
2. What are the data types in JavaScript?
- The data types in JavaScript include numbers, strings, booleans, null, undefined, objects, and symbols.
3. What is the difference between == and === in JavaScript?
- The == operator compares the values of two operands, while the === operator compares both the values and the data types of the operands.
4. What is hoisting in JavaScript?
- Hoisting is a JavaScript behavior where variable and function declarations are moved to the top of their respective scopes, allowing them to be used before they are declared.
5. What is the purpose of the this keyword in JavaScript?
- The this keyword refers to the current object or context in which the current code is executing, and can be used to access or modify object properties and methods.
6. What are closures in JavaScript?
- Closures are functions that have access to variables in their outer scope, even after the outer function has returned.
7. What is the purpose of the bind() method in JavaScript?
- The bind() method is used to create a new function that is bound to a specific object or context, allowing the function to be called with that object as its this value.
8. What is the purpose of the call() method in JavaScript?
- The call() method is used to invoke a function with a specific this value and arguments, allowing the function to be called with a different context than the one in which it was defined.
9. What is the purpose of the apply() method in JavaScript?
- The apply() method is used to invoke a function with a specific this value and an array of arguments, allowing the function to be called with a variable number of arguments.
10. What is event bubbling in JavaScript?
- Event bubbling is a behavior where events that are triggered on a nested element are propagated up through the parent elements in the DOM tree, allowing them to be handled by multiple elements.
That’s all, now you have good knowledge about the most common JavaScript questions being asked in interviews.
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