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Basic  \n2 How do you check the data type of a variable? Basic  \n© 2025 NamasteDev  \nEmpowering developers to build, learn, and grow  \n1/109  \n\n| No.   | Questions   | Level   |\n| --- | --- | --- |\n| 3   | What’s the difference between a JavaScript variable that is:null , unde fi ned or undeclared?     | Basic   |\n| 4   | What are the differences between JavaScript variablescreated using let , var or const ?      | Basic   |\n| 5   | Why is it, in general, a good idea to leave the globalJavaScript scope of a website as-is and never touch it?   | Intermediate   |\n| 6   | How do you convert a string to a number in JavaScript?   | Basic   |\n| 7   | What are template literals and how are they used?   | Basic   |\n| 8   | Explain the concept of tagged templates   | Intermediate   |\n| 9   | What is the spread operator and how is it used?   | Basic   |\n| 10   | What are Symbol s used for in JavaScript?    | Intermediate   |\n| 11   | What are proxies in JavaScript used for?   | Advanced   |\n| 12   | Explain the concept of “hoisting” in JavaScript   | Basic   |\n| 13   | Explain the difference in hoisting between var , let , and  const   | Basic   |\n| 14   | How does hoisting affect function declarations andexpressions?   | Advanced   |\n| 15   | What are the potential issues caused by hoisting?   | Intermediate   |\n| 16   | How can you avoid problems related to hoisting?   | Basic   |\n| 17   | What is the difference between == and = = = in JavaScript?      | Basic   |\n| 18   | What language constructs do you use for iterating overobject properties and array items in JavaScript?   | Basic   |\n| 19   | What is the purpose of the break and continue  statements?   | Basic   |\n| 20   | What is the ternary operator and how is it used?   | Basic   |\n\n© 2025 NamasteDev  \nEmpowering developers to build, learn, and grow  \n2/109  \n\n| No.   | Questions   | Level   |\n| --- | --- | --- |\n| 21   | How do you access the index of an element in an arrayduring iteration?   | Basic   |\n| 22   | What is the purpose of the switch statement?    | Basic   |\n| 23   | What are rest parameters and how are they used?   | Basic   |\n| 24   | Explain the concept of the spread operator and its uses   | Basic   |\n| 25   | What are the benefits of using spread syntax in JavaScriptand how is it different from rest syntax?   | Basic   |\n| 26   | What are iterators and generators in JavaScript and what arethey used for?   | Advanced   |\n| 27   | Explain the differences on the usage of foo between function foo() {} and var foo = fu nction() {} in  JavaScript   | Basic   |\n| 28   | What is the difference between a parameter and anargument?   | Basic   |\n| 29   | Explain the concept of hoisting with regards to functions   | Basic   |\n| 30   | What’s the difference between . call  and . apply  inJavaScript?   | Basic   |\n| 31   | Can you offer a use case for the new arrow => functionsyntax?   | Basic   |\n| 32   | Difference between: function Person(){} , const person = Person() , and const person = new Person() in    \u003Cbr>JavaScript?  \u003Cbr>   | Basic   |\n| 33   | What is the definition of a higher-order function inJavaScript?   | Basic   |\n| 34   | What are callback functions and ho","cbCaicvvKe7vV5Ed","https://ap.wps.com/l/cbCaicvvKe7vV5Ed","pdf",2878607,109,"English","# Who This Guide Is For\n# JavaScript Fundamentals\n## Data types and type checking\n## Variables and scope\n# Core Concepts and Operators\n## Hoisting\n## Equality and iteration\n# Functions and Modern Syntax\n## Hoisting in functions\n## Call, apply, and arrow functions\n# Objects and Copy Semantics\n## Object creation, properties, and descriptors\n## Shallow vs deep copy\n# Advanced Topics\n## Proxies, iterators, and generators","[{\"question\":\"Who is this JavaScript interview guide intended for?\",\"answer\":\"It is designed for frontend developers preparing for interviews, backend engineers working with Node.js, developers transitioning into JavaScript from other languages, and engineers aiming to strengthen their JavaScript skills.\"},{\"question\":\"Which core JavaScript topics are included in the question list?\",\"answer\":\"The guide includes topics such as data types, variable declarations, hoisting, equality comparisons, iteration constructs, and ternary operators, progressing from basic to advanced levels.\"},{\"question\":\"Does the guide cover advanced JavaScript concepts beyond basics?\",\"answer\":\"Yes. It includes advanced subjects such as proxies, tagged templates, iterators and generators, and detailed discussion of object property descriptors and related features.\"}]","JavaScript Interview Questions Guide - Comprehensive Preparation | PDF",1790358483,275]