"Top 25 Programming Interview Questions for JavaScript Developers"

Here the list of top programming #interview questions: Get all these free on interviewdepth.com 1. Reverse a String 2. Check if a String is a Palindrome 3. Remove Duplicates from a String 4. Find the First Non-Repeating Character 5. Count the Occurrences of Each Character 6. Reverse Words in a Sentence 7. Check if Two Strings are Anagrams 8. Find the Longest Substring Without Repeating Characters 9. Convert a String to an Integer (atoi Implementation) 10. Compress a String (Run-Length Encoding) 11. Find the Most Frequent Character 12. Find All Substrings of a Given String 13. Check if a String is a Rotation of Another String 14. Remove All White Spaces from a String 15. Check if a String is a Valid Shuffle of Two Strings 16. Convert a String to Title Case 17. Find the Longest Common Prefix 18. Convert a String to a Character Array 19. Replace Spaces with %20 (URL Encoding) 20. Convert a Sentence into an Acronym 21. Check if a String Contains Only Digits 22. Find the Number of Words in a String 23. Remove a Given Character from a String 24. Find the Shortest Word in a String 25. Find the Longest Palindromic Substring #javascript #javascriptdeveloper #reactjs #reactnative #vuejsdeveloper #angular #angulardeveloper

📝 JavaScript Interview Coding Task Question – Day 73 Look at this code snippet 👇 ✅ Answer & Explanation: Parent constructor Child constructor Hello from Parent Hello from Child 1️⃣ The super keyword in classes is used to call methods on the parent class. 2️⃣ In the Child class, the constructor calls super() → this triggers the Parent constructor first before accessing this. 3️⃣ When child.sayHello() is called, it uses the overridden method in Child, but inside it, super.sayHello() invokes the parent’s version. 4️⃣ The output shows how inheritance chains both constructors and methods, combining parent and child logic. ✨ Tip: 👉 Always call super() before using this in a subclass constructor. 👉 super.method() helps reuse parent logic without rewriting it. #100DaysOfCode #JavaScript #Frontend #WebDevelopment #CodingInterview #JSClasses #Inheritance #DailyCoding #LearnInPublic #kirantechnophile

🟢 #Mastering #JavaScript #Arrays: #Essential #Methods You Should Know 📝If you work with JavaScript, arrays are your best friend. But knowing the right methods can make your code cleaner, faster, and much more readable. Here are some essentials: #push() – Add elements to the end of an array. #pop() – Remove the last element. #shift() – Remove the first element. #sort() – Arrange elements alphabetically or numerically. #indexOf() – Find the first index of an element, or -1 if it’s missing. #lastIndexOf() – Find the last index of an element. 💡 Knowing these can save your time and help to write more efficient, readable code. 🔔 Follow: Code Harvester for more Updates.🎯 ♻ Repost to help others find it. 💾Save this post for future reference. Document credit goes to the respective owner. #JavaScript #Array #UI #WebDevelopment #CodingTips #Programming #CodeHarvester #Developer #coding #programming #softwaredevelopment

learn the top 20 javascript concepts every developer must master All explained simply and practically in this tutorial. From hoisting and closures to async/await, event loop, and prototypes, this guide covers everything you need to build a strong foundation in javascript. each concept is explained with key points, making it perfect for beginners, frontend developers, and anyone preparing for javascript interviews. . . . . 📘 what’s inside: ~hoisting and execution context ~this keyword and lexical scope ~promises & async/await ~prototypes & inheritance ~memory management & event loop ~debounce & throttle functions ~destructuring, spread, and rest operators . . . . . . . #javascript #javascripttutorial #learnjavascript #frontenddeveloper #webdevelopment #programming #coding #developerlife #webdeveloper #frontenddevelopment #reactjs #nodejs #webdesign #softwaredevelopment #codingforbeginners #learncoding #javascriptconcepts #asyncawait #closures #eventloop

## 🚀 **Top 10 JavaScript Concepts Every Developer Should Know!** 💛 JavaScript is the heart of web development — mastering its core concepts makes you a real problem-solver! Let’s quickly revisit some powerful fundamentals 👇 --- ### 🧩 1️⃣ **Variables (`var`, `let`, `const`)** * `var` → Function-scoped * `let`, `const` → Block-scoped * Use `const` when the value won’t change. ```js let name = "Vijaya"; const age = 25; ``` --- ### ⚡ 2️⃣ **Hoisting** Variables and functions are moved to the top of their scope before execution. ```js console.log(x); // undefined var x = 5; ``` --- ### 🌀 3️⃣ **Closures** A function “remembers” the variables from its parent scope — even after the parent is gone! ```js function outer() { let count = 0; return function inner() { count++; console.log(count); }; } const counter = outer(); counter(); // 1 counter(); // 2 ``` --- ### 🧠 4️⃣ **Promises & Async/Await** Handle asynchronous code neatly. ```js async function getData() { const data = await fetch('https://api.example.com'); console.log('Data loaded!'); } ``` --- ### 🧮 5️⃣ **Array Methods** Powerful one-liners for clean code: * `map()` – transform data * `filter()` – filter elements * `reduce()` – combine values ```js let nums = [1,2,3]; let doubled = nums.map(n => n*2); ``` --- ### 🔁 6️⃣ **Callback Functions** A function passed as an argument to another function. ```js function greet(name, callback) { callback(`Hello ${name}`); } greet("Vijaya", console.log); ``` --- ### 🧱 7️⃣ **Objects & Destructuring** Extract values easily: ```js const user = {name: "Vijaya", age: 22}; const {name, age} = user; ``` --- ### 🔥 8️⃣ **ES6 Features** Modern JavaScript = cleaner syntax! ✅ Template literals ✅ Arrow functions ✅ Spread & Rest operators ✅ Modules ```js const arr = [1, 2]; const newArr = [...arr, 3]; ``` --- ### 🧭 9️⃣ **Event Loop** JS is single-threaded but handles async tasks smartly. 📚 Tasks go to the callback queue and execute when the main thread is free. --- ### 💥 🔟 **DOM Manipulation** Make your webpage dynamic! ```js document.getElementById("demo").innerText = "Hello JS!"; ``` --- ### ✨ **Final Thought** > “Knowing syntax is easy — understanding concepts makes you a real developer.” Keep practicing, keep building 💪 #JavaScript #WebDevelopment #CodingJourney #LearnWithMe #FrontendDeveloper #LinkedInLearning #100DaysOfCode Ajay Babu Sappa 10000 Coders sanjeev ch Manivardhan Jakka

📝 JavaScript Interview Coding Task Question – Day 72 Look at this code snippet 👇 ✅ Answer & Explanation: 1️⃣ Object.create(proto) creates a new object whose prototype is proto. It does not call a constructor function. 2️⃣ So child.name → "Kiran" because JavaScript looks up the prototype chain (since child doesn’t have its own name). 3️⃣ After setting child.name = "Sai", the name property is now created on child itself — it shadows the prototype’s property. 4️⃣ proto.name remains "Kiran", proving that child and proto are independent objects connected by prototype inheritance. ✨ Tip: 👉 Object.create() is great for lightweight inheritance without constructors. 👉 Property lookups follow the prototype chain, but assignments always go to the current object unless explicitly modified on the prototype. #100DaysOfCode #JavaScript #Frontend #WebDevelopment #CodingInterview #JSChallenges #LearnInPublic #DailyCoding #kirantechnophile

💻✨ JavaScript Function Practice – Task Completed! This week, I focused on improving my function-building skills in JavaScript through hands-on coding challenges. Each task helped me apply logic, handle edge cases, and write cleaner, reusable code. Here’s what I worked on 👇 🟢 1. Greeting Function greetUser(name, times) — Greets a user multiple times and shows a warning if the count is invalid. 🟢 2. Rectangle Area & Perimeter calcRectangle(width, height) — Returns both area and perimeter of a rectangle, with error handling for invalid dimensions. 🟢 3. Flexible String Repeater repeatString(str, count, separator) — Builds a repeated string with a custom or default separator. 🟢 4. Parameterized Filter Function filterByLength(wordList, minLen, maxLen) — Filters an array of strings based on minimum and maximum word lengths, automatically swapping limits if needed. 🟢 5. Parameterized Calculator Function calculate(a, b, operation) — Performs add, subtract, multiply, or divide operations with smart error handling for zero division or invalid inputs. Each task strengthened my understanding of: ✅ Function parameters & return values ✅ Error handling & validation ✅ Logical problem-solving 💬 Excited to keep practicing and building more JavaScript-based utilities! #JavaScript #CodingPractice #WebDevelopment #ProblemSolving #LearnToCode #Functions #DeveloperJourney #JS #Coding #Coding #10000coders #spandanachowdary #MeghanaM

✅ What is HTML? HTML stands for HyperText Markup Language. It is the standard language used to create and structure webpages. HTML is not a programming language — it is a markup language that tells the browser how to display content. 🧩 What does HTML do? It structures the content on a webpage, such as: Headings Paragraphs Images Links Lists Tables Forms 🔗 HTML + CSS + JavaScript HTML alone = structure CSS = style and colors JavaScript = interaction and behavior Together → complete web development #HTML #CODING #JAVASCRIPT #PYTHON #CSS #REACT

💻✨ Mastering DOM Manipulation in JavaScript! Today, I explored how JavaScript interacts with the HTML structure using the Document Object Model (DOM) — a core skill for every front-end developer. 🚀 🧠 What I Practiced: 🔹 Selecting elements using getElementById(), getElementsByClassName(), getElementsByTagName(), and querySelector() 🔹 Modifying web content with innerText and innerHTML 🔹 Dynamically updating text and HTML elements without refreshing the page This hands-on session helped me understand how JavaScript brings life to web pages by making them interactive and dynamic! 💪 📸 Here’s a glimpse of my DOM learning project in VS Code 👇 Harish M.Spandana Chowdary,Bhagavathula Srividya,10000 Coders #JavaScript #DOMManipulation #FrontendDevelopment #WebDevelopment #HTML #CSS #Coding #Programming #Developer #SoftwareEngineering #LearnToCode #100DaysOfCode #WebDesign #Tech #CodeNewbie #Programmer #JavaScriptDeveloper #FrontendEngineer #WomenWhoCode #FullStackDeveloper #WebDevJourney #CodingLife #TechLearning #CodeWithMe #Developers #StudentDeveloper #VSCode #LearningJourney

Thinking Beyond the Code:- Anyone can learn to write code. But not everyone learns to understand what they’re building. Real developers don’t just chase syntax — they chase purpose, logic, and clarity. Every function, every component, every pixel — it all connects to a bigger picture. Because writing code is easy. But building something meaningful? That takes vision. #DeveloperMindset #FrontendDeveloper #CodeWisely #JavaScript #WebDevelopment #KeepLearning #BuildWithPurpose