JavaScript Interview Questions and Concepts

2 days crash JavaScript prep for interview. I’d split it cleanly: Day 1 → JavaScript (deep fundamentals) Day 2 → Framework / Library + machine coding Because if JavaScript reasoning is weak, no framework knowledge will save you. Day 1: JavaScript (go deep, not wide) These are the high-ROI JavaScript topics I would focus on. Not to memorize but to be able to explain, reason, and handle follow-ups. Execution & Scope - Execution context & call stack - var, let, const (scope + hoisting + TDZ) - Lexical scope - Closures (real bugs, not definitions) Functions & this - this binding (default, implicit, explicit, new) - call, apply, bind - Arrow functions vs normal functions - Function currying & partial application (conceptually) Async JavaScript - Event loop (call stack, task queue, microtasks) - Promises & chaining - async / await (error handling, sequencing) - Race conditions & stale closures - setTimeout, setInterval, requestAnimationFrame Data & References - == vs ===, truthy / falsy values - Object & array references - Deep vs shallow copy - Array methods (map, filter, reduce, find, some, every) ES6+ Core - Destructuring (edge cases & defaults) - Rest vs spread - Map, Set, WeakMap, WeakSet (why they exist) Browser & Runtime (JS-centric) - DOM events & event delegation - Debouncing vs throttling - Memory leaks in JavaScript (closures, listeners, DOM) - Why some things cannot be polyfilled You don’t need to master everything here. But for each topic, you should be able to answer: Why does this exist? Where does this break? What happens if the interviewer changes one condition? That’s Day 1 done properly. Day 2 then becomes easier. Framework concepts, React patterns, and machine coding sit on top of this foundation. If Day 1 is weak, Day 2 collapses quickly. My eBook will save you weeks of scattered prep. 📘 300+ JS and ReactJS questions 📘 60 System Design Question (HLD and LLD) 👉✅️Grab ebook here: https://lnkd.in/g9hdUJkf That’s how you go from writing UI to building robust, scalable, and performant frontend systems. #FrontendInterview #WebDevelopment #JavaScript #ReactJS #CodingTips #FrontendEngineer #TechCareers

✍️ JavaScript Handwritten Notes That Actually Help You Understand JS In a world full of tutorials, reels, and cheat sheets… Handwritten notes still work best when you want real understanding. While preparing for interviews and working on real projects, I realized one thing: 👉 Writing JavaScript concepts by hand forces you to slow down, think, and connect ideas. That’s why I created JavaScript Handwritten Notes — focused on clarity, depth, and interviews. 📘 What These Handwritten Notes Cover 🔹 JavaScript Fundamentals • Data types (primitive vs non-primitive) • var, let, const — scope & hoisting • Truthy & falsy values • Type coercion (== vs ===) 🔹 Execution & Memory Model • How JavaScript code is executed • Execution context & call stack • Hoisting explained visually • Scope chain & lexical environment 🔹 Functions & Closures • Function declaration vs expression • Arrow functions & this behavior • Closures (with real-world examples) • Higher-order functions 🔹 Asynchronous JavaScript • Callbacks & callback hell • Promises — states & chaining • async / await behind the scenes • Event loop (microtasks vs macrotasks) 🔹 Objects, Prototypes & OOP • Object creation patterns • Prototypal inheritance • this, call, apply, bind • Classes vs constructor functions 🔹 Arrays & Important Methods • map, filter, reduce (deep dive) • Shallow vs deep copy • Common JS interview programs 🧠 Why Handwritten Notes Work ✔ Concepts stay longer in memory ✔ Easy to revise before interviews ✔ Great for last-minute prep ✔ Helps you explain clearly in interviews Interviewers don’t test syntax. They test how well you understand what’s happening under the hood. 🎯 Who Are These Notes For? • Beginners struggling with JavaScript • Frontend developers preparing for interviews • Anyone who wants to strengthen JS fundamentals 📌 Final Thought If JavaScript feels confusing, don’t switch tutorials — switch your learning method. Pick a pen ✍️ Write it down Understand it once, properly. 𝑆𝑎𝑣𝑒 𝑡ℎ𝑖𝑠 𝑝𝑜𝑠𝑡 📌  𝑆ℎ𝑎𝑟𝑒 𝑖𝑡 𝑤𝑖𝑡ℎ 𝑠𝑜𝑚𝑒𝑜𝑛𝑒 𝑙𝑒𝑎𝑟𝑛𝑖𝑛𝑔 𝐽𝑎𝑣𝑎𝑆𝑐𝑟𝑖𝑝𝑡 🚀 𝗜 𝗵𝗮𝘃𝗲 𝗽𝗿𝗲𝗽𝗮𝗿𝗲𝗱 𝗖𝗼𝗺𝗽𝗹𝗲𝘁𝗲 𝗜𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄 𝗣𝗿𝗲𝗽𝗮𝗿𝗮𝘁𝗶𝗼𝗻 𝗚𝘂𝗶𝗱𝗲 𝗳𝗼𝗿 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿. 𝗚𝗲𝘁 𝘁𝗵𝗲 𝗚𝘂𝗶𝗱𝗲 𝗵𝗲𝗿𝗲 👉 https://lnkd.in/dygKYGVx 𝗜’𝘃𝗲 𝗯𝘂𝗶𝗹𝘁 𝟴+ 𝗿𝗲𝗰𝗿𝘂𝗶𝘁𝗲𝗿-𝗿𝗲𝗮𝗱𝘆 𝗽𝗼𝗿𝘁𝗳𝗼𝗹𝗶𝗼 𝘄𝗲𝗯𝘀𝗶𝘁𝗲𝘀 𝗳𝗼𝗿 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿𝘀. 𝗚𝗲𝘁 𝘁𝗵𝗲 𝗽𝗼𝗿𝘁𝗳𝗼𝗹𝗶𝗼𝘀 𝗵𝗲𝗿𝗲 👉 https://lnkd.in/drqV5Fy3 #JavaScript #JavaScriptNotes #HandwrittenNotes #FrontendDeveloper #WebDevelopment #InterviewPreparation #Programming #SoftwareEngineer

You know a lot of JavaScript but when the interview is in 2 days, you don’t know what to revise. Don't panic, just follow this plan. That confusion is very real, especially for experienced developers. You’re not short on knowledge. You’re short on time and prioritization. When timelines are tight, the goal is not to “revise everything”. It’s to stabilize the parts interviews actually build on. Here’s a 2-day revision plan that’s realistic and well-rounded. Day 1: Make your foundation unshakable 1️⃣ Execution & scope var, let, const hoisting & TDZ closures & lexical environment If this is shaky, explanations collapse under follow-ups. 2️⃣ Function behavior this binding (default, implicit, explicit) call / apply / bind arrow functions (what changes, what doesn’t) Interviewers use this to test depth very quickly. 3️⃣ ES6 essentials (high ROI only) Destructuring rest vs spread default parameters Map vs Object, Set vs Array Not syntax but behavior and use-cases. Day 2: Timing, async, and real-world behavior 4️⃣ Async behavior event loop (call stack, task queue, microtasks) promises & chaining async / await error handling stale closures Most “why does this behave weirdly?” questions come from here. 5️⃣ Data & references == vs ===, truthy / falsy deep vs shallow copy object & array references array methods (map, filter, reduce, find, some, every) This exposes real understanding instantly. 6️⃣ Browser & network basics DOM events & event delegation debouncing vs throttling reflow vs repaint (high level) Fetch API, AbortController CORS (what frontend controls vs what it doesn’t) Frontend interviews rarely stay “pure JS”. How to revise (this matters more than the list) For every topic, don’t memorize. Ask yourself: Why does this exist? What breaks if I misuse it? Where have I seen this bug in real code? If you can explain it calmly without notes, it’s ready. If not, that’s what you revise not the next topic. If you want a structured way to revise these fundamentals, I’ve covered them end-to-end in The JavaScript Masterbook: Grab the list here (most commonly asked interview questions): 👉 https://lnkd.in/gyB9GjBt ✅ 180+ interview questions with deep explanations ✅ Real-world examples + practice questions ✅ Designed to build understanding, not just recognition #frontend #javascript #reactjs #interviewpreparation #frontenddeveloper #webdevelopment #career

You know a lot of JavaScript but when the interview is in 2 days, you don’t know what to revise. Don't panic, just follow this plan. That confusion is very real, especially for experienced developers. You’re not short on knowledge. You’re short on time and prioritization. When timelines are tight, the goal is not to “revise everything”. It’s to stabilize the parts interviews actually build on. Here’s a 2-day revision plan that’s realistic and well-rounded. Day 1: Make your foundation unshakable 1️⃣ Execution & scope var, let, const hoisting & TDZ closures & lexical environment If this is shaky, explanations collapse under follow-ups. 2️⃣ Function behavior this binding (default, implicit, explicit) call / apply / bind arrow functions (what changes, what doesn’t) Interviewers use this to test depth very quickly. 3️⃣ ES6 essentials (high ROI only) Destructuring rest vs spread default parameters Map vs Object, Set vs Array Not syntax but behavior and use-cases. Day 2: Timing, async, and real-world behavior 4️⃣ Async behavior event loop (call stack, task queue, microtasks) promises & chaining async / await error handling stale closures Most “why does this behave weirdly?” questions come from here. 5️⃣ Data & references == vs ===, truthy / falsy deep vs shallow copy object & array references array methods (map, filter, reduce, find, some, every) This exposes real understanding instantly. 6️⃣ Browser & network basics DOM events & event delegation debouncing vs throttling reflow vs repaint (high level) Fetch API, AbortController CORS (what frontend controls vs what it doesn’t) Frontend interviews rarely stay “pure JS”. How to revise (this matters more than the list) For every topic, don’t memorize. Ask yourself: Why does this exist? What breaks if I misuse it? Where have I seen this bug in real code? If you can explain it calmly without notes, it’s ready. If not, that’s what you revise not the next topic. If you want a structured way to revise these fundamentals, I’ve covered them end-to-end in The JavaScript Masterbook: Grab the list here (most commonly asked interview questions): 👉 https://lnkd.in/gyB9GjBt ✅ 180+ interview questions with deep explanations ✅ Real-world examples + practice questions ✅ Designed to build understanding, not just recognition #frontend #javascript #reactjs #interviewpreparation #frontenddeveloper #webdevelopment #career

You know a lot of JavaScript but when the interview is in 2 days, you don’t know what to revise. Don't panic, just follow this plan. That confusion is very real, especially for experienced developers. You’re not short on knowledge. You’re short on time and prioritization. When timelines are tight, the goal is not to “revise everything”. It’s to stabilize the parts interviews actually build on. Here’s a 2-day revision plan that’s realistic and well-rounded. Day 1: Make your foundation unshakable 1️⃣ Execution & scope var, let, const hoisting & TDZ closures & lexical environment If this is shaky, explanations collapse under follow-ups. 2️⃣ Function behavior this binding (default, implicit, explicit) call / apply / bind arrow functions (what changes, what doesn’t) Interviewers use this to test depth very quickly. 3️⃣ ES6 essentials (high ROI only) Destructuring rest vs spread default parameters Map vs Object, Set vs Array Not syntax but behavior and use-cases. Day 2: Timing, async, and real-world behavior 4️⃣ Async behavior event loop (call stack, task queue, microtasks) promises & chaining async / await error handling stale closures Most “why does this behave weirdly?” questions come from here. 5️⃣ Data & references == vs ===, truthy / falsy deep vs shallow copy object & array references array methods (map, filter, reduce, find, some, every) This exposes real understanding instantly. 6️⃣ Browser & network basics DOM events & event delegation debouncing vs throttling reflow vs repaint (high level) Fetch API, AbortController CORS (what frontend controls vs what it doesn’t) Frontend interviews rarely stay “pure JS”. How to revise (this matters more than the list) For every topic, don’t memorize. Ask yourself: Why does this exist? What breaks if I misuse it? Where have I seen this bug in real code? If you can explain it calmly without notes, it’s ready. If not, that’s what you revise not the next topic. If you want a structured way to revise these fundamentals, I’ve covered them end-to-end in The JavaScript Masterbook: Grab the list here (most commonly asked interview questions): 👉 https://lnkd.in/gyB9GjBt ✅ 180+ interview questions with deep explanations ✅ Real-world examples + practice questions ✅ Designed to build understanding, not just recognition #frontend #javascript #reactjs #interviewpreparation #frontenddeveloper #webdevelopment #career

50 #JavaScript Interview Questions (All in One Post) 1. What is the difference between var, let, and const?   2. How does JavaScript handle hoisting?   3. What is the Temporal Dead Zone (TDZ)?   4. Explain closures with a real-life example (e.g., private counter or module pattern).   5. What is the difference between == and ===? (Bonus: When might loose equality be useful?)   6. What are all the JavaScript data types (primitives + objects)?   7. What is NaN and how do you reliably check for it?   8. What is the event loop in JavaScript? Describe the call stack, Web APIs, task queues.   9. Explain microtasks vs macrotasks with examples.   10. What is the difference between synchronous and asynchronous code?   11. What are promises and why were they introduced (callback hell killer)?   12. Difference between async/await and .then() chaining? Pros/cons?   13. What happens if a promise is neither resolved nor rejected (pending forever)?   14. What is callback hell and how do modern patterns avoid it?   15. What is the purpose of setTimeout and setInterval? How accurate are they?   16. How does 'this' work in different contexts (global, object, constructor, strict mode)?   17. What is the difference between arrow functions and regular functions (this, arguments, constructor)?   18. What is function currying? Write a simple curry example.   19. What are higher-order functions? Give 3 array method examples.   20. Explain call(), apply(), and bind() with use cases.   21. What is prototypal inheritance?   22. Difference between Object.freeze() and Object.seal()?   23. What is the prototype chain? How does lookup work?   24. What are shallow copy vs deep copy? When does it matter?   25. How do you clone an object in JavaScript (shallow & deep methods)?   26. What is destructuring (object & array)? Nested example?   27. What is the spread operator (...) and rest parameter? Differences?   28. What are template literals and tagged templates?   29. What is optional chaining (?.) and when to use it?   30. What is nullish coalescing (??) vs logical OR (||)?   31. Difference between map(), filter(), and reduce()? When to choose each?   32. What is debouncing vs throttling? Implement a debounce function.   33. What is memoization? Why & how to implement it?   34. What is event delegation? Why is it better than attaching listeners to each element?   35. Difference between for...in and for...of? When to use each?   36. What is strict mode ('use strict')? What bugs does it prevent?   37. Difference between undefined and null? (typeof surprises?)   38. What are IIFEs (Immediately Invoked Function Expressions)? Modern alternatives?   39. What is a pure function? Why prefer them?   40. What are side effects in JavaScript? Examples?  Rest are in comments Follow Ankit Sharma for more such insights. #JavaScript #JSInterview #Frontend #WebDevelopment #CodingInterview #Developers #LearnJavaScript #InterviewPrep #ES6 #AsyncJavaScript #UttarPradeshTech #TechJobs2026

Commonly asked JavaScript interview questions. 𝗖𝗼𝗿𝗲 𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁 1. What is the difference between var, let, and const in JavaScript? 2. What are closures in JavaScript, and how do they work? 3. What is the this keyword in JavaScript, and how does it behave in different contexts? 4. What is a JavaScript promise, and how does it handle asynchronous code? 5. What is the event loop, and how does JavaScript handle asynchronous operations? 6. What is hoisting in JavaScript, and how does it work? 7. What are JavaScript data types, and how do you check the type of a variable? 8. What is the difference between null and undefined in JavaScript? 9. What is a callback function, and how is it used? 10. How do you manage errors in JavaScript? 𝗔𝘀𝘆𝗻𝗰 𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁 11. What is the difference between setTimeout() and setInterval()? 12. How do JavaScript promises work, and what is the then() method? 13. What is async/await, and how does it simplify asynchronous code in JavaScript? 14. What are the advantages of using async functions over callbacks? 15. How do you handle multiple promises simultaneously? 𝗙𝗮𝗻𝗰𝘆 𝗙𝗲𝗮𝘁𝘂𝗿𝗲𝘀 𝗶𝗻 𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁 16. What are higher-order functions in JavaScript, and can you provide an example? 17. What is destructuring in JavaScript, and how is it useful? 18. What are template literals in JavaScript, and how do they work? 19. How does the spread operator work in JavaScript? 20. What is the rest parameter in JavaScript, and how does it differ from the arguments object? 𝗢𝗯𝗷𝗲𝗰𝘁𝘀 𝗮𝗻𝗱 𝗔𝗿𝗿𝗮𝘆𝘀 21. What is the difference between an object and an array in JavaScript? 22. How do you clone an object or array in JavaScript? 23. What are object methods like Object.keys(), Object.values(), and Object.entries()? 24. How does the map() method work in JavaScript, and when would you use it? 25. What is the difference between map() and forEach() in JavaScript? 𝗦𝗽𝗲𝗰𝗶𝗮𝗹 𝗧𝗵𝗲𝗼𝗿𝘆 26. What is event delegation in JavaScript, and why is it useful? 27. What are JavaScript modules, and how do you import/export them? 28. What is the prototype chain in JavaScript, and how does inheritance work? 29. What is bind(), call(), and apply() in JavaScript, and when do you use them? 30. How does JavaScript handle equality comparisons with == and ===? 𝗖𝗼𝗻𝗰𝗲𝗽𝘁𝘀 𝗶𝗻 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 31. What is the Document Object Model (DOM), and how does JavaScript interact with it? 32. How do you prevent default actions and stop event propagation in JavaScript? 33. What is the difference between an event object and a custom event in JavaScript? 34. How do you optimize performance in JavaScript applications? ----------------------------------- Join devs on • 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱 𝗖𝗶𝗿𝗰𝗹𝗲 𝗯𝘆 𝗦𝗮𝗸𝘀𝗵𝗶 → https://lnkd.in/d45J2fuv   • 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱 𝗧𝗼𝗱𝗮𝘆 → https://lnkd.in/dK94iu7Y Follow Sakshi Gawande for more such content 💓

40 #JavaScript Interview Questions 1. What is the difference between var, let, and const? 2. How does JavaScript handle hoisting? 3. What is the Temporal Dead Zone (TDZ)? 4. Explain closures with a real-life example (e.g., private counter or module pattern). 5. What is the difference between == and ===? (Bonus: When might loose equality be useful?) 6. What are all the JavaScript data types (primitives + objects)? 7. What is NaN and how do you reliably check for it? 8. What is the event loop in JavaScript? Describe the call stack, Web APIs, task queues. 9. Explain microtasks vs macrotasks with examples. 10. What is the difference between synchronous and asynchronous code? 11. What are promises and why were they introduced (callback hell killer)? 12. Difference between async/await and .then() chaining? Pros/cons? 13. What happens if a promise is neither resolved nor rejected (pending forever)? 14. What is callback hell and how do modern patterns avoid it? 15. What is the purpose of setTimeout and setInterval? How accurate are they? 16. How does 'this' work in different contexts (global, object, constructor, strict mode)? 17. What is the difference between arrow functions and regular functions (this, arguments, constructor)? 18. What is function currying? Write a simple curry example. 19. What are higher-order functions? Give 3 array method examples. 20. Explain call(), apply(), and bind() with use cases. 21. What is prototypal inheritance? 22. Difference between Object.freeze() and Object.seal()? 23. What is the prototype chain? How does lookup work? 24. What are shallow copy vs deep copy? When does it matter? 25. How do you clone an object in JavaScript (shallow & deep methods)? 26. What is destructuring (object & array)? Nested example? 27. What is the spread operator (...) and rest parameter? Differences? 28. What are template literals and tagged templates? 29. What is optional chaining (?.) and when to use it? 30. What is nullish coalescing (??) vs logical OR (||)? 31. Difference between map(), filter(), and reduce()? When to choose each? 32. What is debouncing vs throttling? Implement a debounce function. 33. What is memoization? Why & how to implement it? 34. What is event delegation? Why is it better than attaching listeners to each element? 35. Difference between for...in and for...of? When to use each? 36. What is strict mode ('use strict')? What bugs does it prevent? 37. Difference between undefined and null? (typeof surprises?) 38. What are IIFEs (Immediately Invoked Function Expressions)? Modern alternatives? 39. What is a pure function? Why prefer them? 40. What are side effects in JavaScript? Examples? #JavaScript #JSInterview #Frontend #WebDevelopment #CodingInterview

🤯 JavaScript Destructuring: More Than Just Renaming At first glance, JavaScript destructuring feels like simple variable renaming. But under the hood, there’s a subtle rule that often shows up in interviews—and trips people up. Let’s break it down 👇 What’s Really Happening? When you write an object destructuring in this pattern: key : target You are not just renaming. You are mapping a source key to a destination. Key → where the value is READ from Target → where the value is ASSIGNED to The target doesn’t have to be a variable. It can also be an object property. That’s why in this case: One value resolves correctly Another ends up as undefined Because JavaScript follows the rule strictly: 👉 Read from the key, assign to the target Output Explained The value is picked from the source object using the key It’s then assigned to a different location If that location doesn’t line up with how you later access it, you’ll see undefined This is valid JavaScript behavior—not a bug. 🧠 Key Takeaway Object destructuring follows this mental model: 📥 Key → source of truth 📤 Target → destination Yes, it looks like renaming. But technically, it’s controlled assignment. That distinction is small—but extremely important in real-world debugging and interviews. 🎯 Why Interviewers Love This Tests deep understanding of syntax Separates memorization from real comprehension Reveals how well you reason about JavaScript behavior Small syntax. Big conceptual payoff. 🖼️ Image Idea (for the attached visual) Create a clean dark-themed code editor mockup showing: A JavaScript object on the right (source) A destructuring statement in the center (key : target) Arrows visually mapping: object.key → target location Console output below highlighting: Correct value undefined result This visually reinforces READ vs ASSIGN. 👉 Follow Rahul R Jain for more real interview insights, React fundamentals, and practical frontend engineering content. #JavaScript #ES6 #Destructuring #FrontendDevelopment #WebDevelopment #ReactJS #ModernJavaScript #LearnInPublic #FrontendEngineer

50 Must-know JavaScript Interview Questions 1. What is Debouncing in JavaScript? 2. Understanding Promise.all() 3. What is Deep Equal? 4. Understanding Event Emitters 5. What is Array.prototype.reduce()? 6. Simplifying arrays – Flattening 7. Merging data structures 8. Selecting DOM Elements – getElementsByClassName 9. Avoiding redundant computations with memoization 10. Safer nested property access: get 11. Hoisting in JavaScript. 12. What are the differences between JavaScript variables created using let, var, and const? 13. Explain the difference between == and === in JavaScript? 14. Understanding the Event Loop in JavaScript. 15. What is Event Delegation in JavaScript? 16. How this works in JavaScript. 17. What sets Cookies, sessionStorage, and localStorage apart? 18. How do <script>, <script async>, and <script defer> differ? 19. What's the difference between null, undefined? 20. What's the difference between .call() vs .apply()? 21. How does Function.prototype.bind work? 22. Why use arrow functions in constructors? 23. How does prototypal inheritance work? 24. Differences between: function Person(){}, const person = Person(), and const person = new Person()? 25. Function declarations vs. Function expressions 26. What are the different ways to create objects in JavaScript? 27. What is a higher-order function? 28. How do ES2015 classes differ from ES5 constructor functions? 29. What is event bubbling? 30. What is event capturing? 31. How do mouseenter and mouseover differ? 32. What's the difference between synchronous and asynchronous functions? 33. What is AJAX? 34. What are the pros and cons of using AJAX? 35. What are the differences between XMLHttpRequest and fetch()? 36. What are the various data types in JavaScript? 37. How do you iterate over object properties and array items? 38. What are the benefits of spread syntax, and how is it different from rest syntax? 39. What are the differences between Maps vs. Plain objects? 40. What are the differences between Map/Set and WeakMap/WeakSet 41. What are practical use cases for arrow functions? 42. What are callback functions in asynchronous operations? 43. What is debouncing and throttling? 44. How does destructuring assignment work? 45. What is function hoisting? 46. How does inheritance work in ES2015 classes? 47. What is lexical scoping? 48. What are scopes in JavaScript? 49. What is the spread operator? 50. How does this work in event handlers? 𝗙𝗼𝗹𝗹𝗼𝘄𝘀 𝘂𝘀 𝗵𝗲𝗿𝗲  → https://lnkd.in/geqez4re