JavaScript Basics: Closures, Hoisting, Event Loop, Promises, and More

𝐌𝐨𝐬𝐭 𝐬𝐭𝐮𝐝𝐞𝐧𝐭𝐬 𝐩𝐫𝐞𝐩𝐚𝐫𝐞 𝐑𝐞𝐚𝐜𝐭 𝐛𝐲 𝐰𝐚𝐭𝐜𝐡𝐢𝐧𝐠 𝐭𝐮𝐭𝐨𝐫𝐢𝐚𝐥𝐬. 𝐁𝐮𝐭 𝐢𝐧𝐭𝐞𝐫𝐯𝐢𝐞𝐰𝐬 𝐭𝐞𝐬𝐭 𝐜𝐥𝐚𝐫𝐢𝐭𝐲, 𝐧𝐨𝐭 𝐣𝐮𝐬𝐭 𝐜𝐨𝐝𝐢𝐧𝐠. So I created a practical resource to help you revise faster. 📘 116 Most Asked React Interview Questions (2026 Edition) Covers everything from Hooks to Performance and Architecture the topics that actually show up in interviews. If you're preparing for frontend or React roles, this will save you hours of scattered searching. Download it, revise a few questions daily, and keep it as your quick revision guide. If this helps you, share it with a friend who is preparing for React interviews. #reactjs #frontend #javascript #interview #placement #coding #softwareengineering

🌺 I noticed many beginners struggle with basic JavaScript interview questions. I created a simple guide to make things easier 💡 📘 20 important questions 📘 Clear, beginner-friendly explanations 📘 No unnecessary complexity The goal is simple: 👉 Help you understand faster 👉 Save your time 👉 Feel more confident in interviews Already 10+ people have downloaded it, which is a good start 🙌 If you’re preparing for interviews, this might help you too. 🎁 It’s free for now (early stage) I’ll be improving it and adding more value soon. 👉 Download it Now:https://lnkd.in/dUePYuvM #javascript #webdevelopment #frontend #coding #interviewprep #learncoding

𝐈𝐟 𝐘𝐨𝐮 𝐂𝐚𝐧 𝐒𝐨𝐥𝐯𝐞 𝐓𝐡𝐞𝐬𝐞 𝐉𝐚𝐯𝐚𝐒𝐜𝐫𝐢𝐩𝐭 𝐐𝐮𝐞𝐬𝐭𝐢𝐨𝐧𝐬, 𝐘𝐨𝐮'𝐫𝐞 𝐈𝐧𝐭𝐞𝐫𝐯𝐢𝐞𝐰-𝐑𝐞𝐚𝐝𝐲 100 real interview questions across the exact topics companies test. Inside this PDF you'll find: • Scope, hoisting, and closures that confuse most candidates • The tricky parts of this that break real interviews • Event loop and async patterns explained with outputs • Prototypes, promises, coercion, and modern JS concepts • Advanced edge cases that interviewers love to ask This is not theory-heavy content. These are the kinds of questions that expose real understanding. If you're preparing for frontend roles, this will help you identify gaps quickly and strengthen fundamentals. Download it, practice a few questions daily, and revisit the ones that challenge you the most. If you find this useful: • Save it for later revision • Share it with someone preparing for interviews • Comment "JS" if you'd like more resources like this More structured resources are coming soon. #frontend #interviews #softwareengineering #coding #placements #javascript

** Technical Interview Question ** Today I worked on a common but important interview question: 🔍 Find the first non-repeating element in an array 👉 Example: [4, 5, 1, 2, 0, 4] 👉 Output: 5 💡 My Approach: 1. First, I counted how many times each element appears 2. Then, I traversed the original array to find the first element that appears only once ⚡ Key Insights: Order matters — that’s why iterating over the original array is important Using a frequency map makes the solution efficient Time Complexity: O(n) Space Complexity: O(n) 🎯 Practicing these types of problems really helps in improving logic building and interview confidence, especially for Frontend / MERN Stack roles. Consistency is the key 🔥 #JavaScript #CodingInterview #ProblemSolving #MERNStack #FrontendDeveloper #ReactJS

🚀 React Interview Question: How do you optimize React Context to reduce unnecessary re-renders? 💡 React Context is a common way to share data across components But if it’s not handled carefully, it can lead to extra re-renders, whenever the context value changes, all the components using it re-render. 🔹 1. Split your Context Don’t put everything in one place - keep contexts small and focused for better performance 🔹 2. Memoize the value Context updates are based on reference changes. - use useMemo to keep the value stable 🔹 3. Avoid inline functions New function creates a new reference, which causes a re-render - use useCallback 🔹 4. Use selector pattern Don’t consume the entire context if you only need one value 🔹 5. Keep state local when possible Not everything needs to live in Context 🔹 6. Use React.memo Helps prevent unnecessary child re-renders 🔹 Key Insight: React Context doesn’t check deep changes It only checks if the reference has changed So to optimize: - keep values stable - split contexts smartly - avoid unnecessary updates Connect/Follow Tarun Kumar for more tech content and interview prep #React #FrontendDevelopment #JavaScript #WebDev #SoftwareEngineering #CodingInterview

150+ interviews given. 50+ interviews taken. I’ve distilled that experience into 20 high-impact Frontend questions — perfect for cracking interviews and quick revision. How to approach them: - Solve before you see the answer - Simulate real interview thinking - Prioritize concepts over memorization - Save your solutions and revisit them later — real learning happens in the second pass - Revisit weak areas - Practice clear explanation (this is where most fail) 📌 I’ll share the full list — link in the comments Hashtags: #frontend #softwareengineering #interviewprep #javascript #reactjs #webdevelopment #careergrowth #techcareers #codinginterview #developers #learninpublic #programming #jobs #engineering #interviewtips

🚀 𝐌𝐨𝐬𝐭 𝐩𝐞𝐨𝐩𝐥𝐞 𝐟𝐚𝐢𝐥 𝐍𝐨𝐝𝐞.𝐣𝐬 𝐢𝐧𝐭𝐞𝐫𝐯𝐢𝐞𝐰𝐬… 𝐧𝐨𝐭 𝐛𝐞𝐜𝐚𝐮𝐬𝐞 𝐭𝐡𝐞𝐲 𝐜𝐚𝐧’𝐭 𝐜𝐨𝐝𝐞. They fail because they forget the fundamentals. If your basics aren’t strong, even simple questions can feel difficult. So I came across a Node.js revision sheet that covers 120+ important questions in one place — perfect for quick prep before interviews. 🔍 𝐖𝐡𝐚𝐭 𝐢𝐭 𝐜𝐨𝐯𝐞𝐫𝐬: ✅ Event Loop, async behavior & non-blocking I/O ✅ Promises, async/await & real-world flow ✅ Express, routing & middleware ✅ Streams, buffers & core modules ✅ JWT authentication & security basics ✅ Scaling, clustering & system design ⚡ 𝐖𝐡𝐲 𝐢𝐭’𝐬 𝐮𝐬𝐞𝐟𝐮𝐥: ↳ Short, concise, and straight to the point ↳ Perfect for last-minute revision ↳ Covers both concepts + practical understanding 🎯 You don’t need more resources — you need to revise the right ones. 💾 Save this now — you’ll thank yourself before your next interview. 🚀 Follow for more practical dev content & resources. #NodeJS #BackendDevelopment #InterviewPrep #JavaScript #Developers #LearnToCode #TechCareers #DevCommunity #FullStackDeveloper #BackendDeveloper

🚨 Most Developers Get This Wrong in React Interviews 👉 Why does a component re-render even when nothing changed? If you can’t confidently answer this… You’re not ready for product-based interviews yet. 💡 React is not just about writing components. It’s about understanding: ⚡ How rendering works ⚡ Why performance issues happen ⚡ How to control re-renders 🔥 Real interview scenarios companies ask: • Why does a child re-render when parent updates? • Why do inline functions cause re-renders? • When does React.memo fail? • useMemo vs useCallback — real difference? • Why does useEffect run twice in React 18? ❌ Most people memorize hooks ✅ Top candidates understand behavior 📄 So I created: 👉 React Re-render & Performance – 30 Scenario-Based Questions This is NOT theory. These are the actual patterns interviewers test. 💬 Comment REACT and I’ll share the PDF #reactjs #frontenddeveloper #javascript #codinginterview #webdevelopment #softwareengineer #reactperformance #learnincode #techcareer #developers #react18 #programming 🚀

3 months habve gone by. If interview prep is still "something you’ll start soon", it probably won’t happen without a plan. Not more effort. Just better structure. Learn, Practice, Apply and Perform. That’s the framework we built our 1-month plan around at GreatFrontEnd. Follow the full plan: https://lnkd.in/gGST2UGw #frontendinterviews #webdevelopment #frontenddevelopment #greatfrontend #javascript

🚀 Just Built Something Powerful for React Interview Prep! I noticed most React interview prep content is either too basic or repetitive… so I decided to fix that. I’ve created a PDF with 30 unique React.js output-based questions that actually test real understanding — not just theory. ✅ Covers real-world concepts • useState (async updates & batching) • useEffect (execution order & dependencies) • Closures & stale state • Memoization (useMemo, useCallback, React.memo) • Keys & reconciliation • Rendering behavior & performance 💡 Each question includes: ✔ Clean, readable code ✔ Exact output ✔ Clear explanation (why it works that way) This is the kind of practice that helps you think like React, not just memorize it. 📌 Perfect for: • Frontend developers preparing for product-based companies • Developers stuck at “I know React but can’t crack interviews” stage If you want the PDF 👉 Comment “React” and I’ll share it with you. #ReactJS #FrontendDevelopment #JavaScript #WebDevelopment #InterviewPreparation #CodingInterview #ReactDeveloper #LearnToCode