ABHAY TEWATIA’s Post

🚀 JavaScript Simplified Series — Day 36 You created a class… Now imagine 👇 You want another class with: 👉 Same properties 👉 Same methods 👉 Plus some extra features Will you rewrite everything again? ❌ That’s inefficient 😵 --- ## 🔥 Solution → Inheritance --- ## 🔹 What is Inheritance? Inheritance allows one class to: 👉 **Reuse properties & methods of another class** --- ## 🔹 Example ```javascript id="inh1" class User { constructor(name) { this.name = name } greet() { console.log("Hello " + this.name) } } class Admin extends User { deleteUser() { console.log("User deleted") } } let admin = new Admin("Abhay") admin.greet() admin.deleteUser() ``` 👉 Output: Hello Abhay User deleted --- ## 🔍 What’s happening? 👉 `Admin` inherited from `User` 👉 So it gets `greet()` automatically 👉 Plus its own method --- ## 🔹 super keyword ```javascript id="inh2" class Admin extends User { constructor(name, role) { super(name) this.role = role } } ``` 👉 `super()` calls parent constructor --- ## 🔥 Real Life Example Think of a **family 👨👩👧** 👉 Parent → basic traits 👉 Child → inherits + adds new traits --- ## 🔥 Simple Summary extends → inheritance super → parent constructor Reuse → no duplication --- ### 💡 Programming Rule **Don’t rewrite code. Reuse it with inheritance.** --- If you want to learn JavaScript in a **simple and practical way**, you can follow these YouTube channels: • Rohit Negi • Hitesh Choudhary (Chai aur Code) --- 📌 Series Progress Day 1 → What is JavaScript Day 2 → Variables & Data Types Day 3 → Type Conversion & Operators Day 4 → Truthy & Falsy + Comparison Operators Day 5 → If Else + Switch + Ternary Day 6 → Loops Day 7 → Break + Continue + Nested Loops Day 8 → Functions Basics Day 9 → Arrow + Default + Rest Parameters Day 10 → Callback & Higher Order Functions Day 11 → Arrays Basics Day 12 → Array Methods Day 13 → Array Iteration Day 14 → Advanced Array Methods Day 15 → Objects Basics Day 16 → Object Methods + this Day 17 → Object Destructuring Day 18 → Spread & Rest Day 19 → Advanced Objects Day 20 → DOM Introduction Day 21 → DOM Selectors Day 22 → DOM Manipulation Day 23 → Events Day 24 → Event Bubbling Day 25 → Event Delegation Day 26 → Async JavaScript Day 27 → Promises Day 28 → Async / Await Day 29 → Fetch API Day 30 → Event Loop Day 31 → Scope Day 32 → Hoisting Day 33 → Closures Day 34 → Prototypes Day 35 → Classes Day 36 → Inheritance Day 37 → Modules (Next Post) --- Follow for more 🚀 #JavaScriptSimplified #javascript #webdevelopment #coding #programming #learninpublic #100DaysOfCode #frontenddevelopment #devcommunity #codingjourney #softwaredeveloper #techcommunity #dailylearning #codeeveryday

🚀 JavaScript Simplified Series — Day 35 Prototypes are powerful… But let’s be honest 😅 👉 Syntax thoda confusing lagta hai 👉 Hard to read 👉 Not beginner friendly What if we could write the same thing in a **clean and simple way?** 🤔 --- ## 🔥 Solution → Classes --- ## 🔹 What are Classes? Classes are just a **clean syntax over prototypes** 👉 Same power 👉 Better readability --- ## 🔹 Without Class (Old Way) ```javascript id="clx1" function User(name) { this.name = name } User.prototype.greet = function() { console.log("Hello " + this.name) } let u1 = new User("Abhay") u1.greet() ``` --- ## 🔹 With Class (Modern Way 😎) ```javascript id="clx2" class User { constructor(name) { this.name = name } greet() { console.log("Hello " + this.name) } } let u1 = new User("Abhay") u1.greet() ``` 👉 Same result 👉 Cleaner code --- ## 🔹 Adding More Methods ```javascript id="clx3" class User { constructor(name) { this.name = name } greet() { console.log("Hello " + this.name) } sayBye() { console.log("Goodbye") } } ``` --- ## 🔥 Real Life Example Think of a **blueprint 🏗️** 👉 Class = blueprint 👉 Object = actual building Same design → multiple objects --- ## 🔥 Simple Summary Class → cleaner syntax Constructor → initialize values Methods → behavior --- ### 💡 Programming Rule **Write code that humans can read. Classes make code cleaner.** --- If you want to learn JavaScript in a **simple and practical way**, you can follow these YouTube channels: • Rohit Negi --- 📌 Series Progress Day 1 → What is JavaScript Day 2 → Variables & Data Types Day 3 → Type Conversion & Operators Day 4 → Truthy & Falsy + Comparison Operators Day 5 → If Else + Switch + Ternary Day 6 → Loops Day 7 → Break + Continue + Nested Loops Day 8 → Functions Basics Day 9 → Arrow + Default + Rest Parameters Day 10 → Callback & Higher Order Functions Day 11 → Arrays Basics Day 12 → Array Methods Day 13 → Array Iteration Day 14 → Advanced Array Methods Day 15 → Objects Basics Day 16 → Object Methods + this Day 17 → Object Destructuring Day 18 → Spread & Rest Day 19 → Advanced Objects Day 20 → DOM Introduction Day 21 → DOM Selectors Day 22 → DOM Manipulation Day 23 → Events Day 24 → Event Bubbling Day 25 → Event Delegation Day 26 → Async JavaScript Day 27 → Promises Day 28 → Async / Await Day 29 → Fetch API Day 30 → Event Loop Day 31 → Scope Day 32 → Hoisting Day 33 → Closures Day 34 → Prototypes Day 35 → Classes Day 36 → Inheritance (Next Post) --- Follow for more 🚀 #JavaScriptSimplified #javascript #webdevelopment #coding #programming #learninpublic #100DaysOfCode #frontenddevelopment #devcommunity #codingjourney #softwaredeveloper #techcommunity #dailylearning #codeeveryday

🚀 JavaScript Simplified Series — Day 32 You used a variable… Before even declaring it 😳 And somehow… it still worked? 🤯 How is that even possible? --- ## 🔥 This is called → Hoisting --- ## 🔹 What is Hoisting? Hoisting means: 👉 JavaScript moves declarations to the **top of their scope** Before execution starts --- ## 🔹 Example (Confusing 😵) ```javascript id="hs1" console.log(x) var x = 10 ``` 👉 Output: undefined 😳 --- ## 🔍 What actually happens? JavaScript internally converts it to: ```javascript id="hs2" var x console.log(x) x = 10 ``` 👉 Declaration upar chali gayi 👉 Value assign baad me hui --- ## 🔹 let & const (Important ⚠️) ```javascript id="hs3" console.log(a) let a = 10 ``` 👉 Error ❌ 📌 Because of **Temporal Dead Zone (TDZ)** --- ## 🔥 What is TDZ? Time between: 👉 Variable declared 👉 Aur initialize hone tak Is duration me access nahi kar sakte --- ## 🔹 Function Hoisting ```javascript id="hs4" greet() function greet() { console.log("Hello") } ``` 👉 Works perfectly ✅ 📌 Functions are fully hoisted --- ## 🔥 Real Life Example Think of a classroom 🏫 👉 Teacher announces names first 👉 Details baad me fill hoti hain 👉 Declaration pehle 👉 Value baad me --- ## 🔥 Simple Summary Hoisting → declarations upar move hoti hain var → undefined milta hai let/const → error (TDZ) function → fully hoisted --- ### 💡 Programming Rule **Always declare variables at the top. Don’t rely on hoisting.** --- If you want to learn JavaScript in a **simple and practical way**, you can follow these YouTube channels: • Rohit Negi • Hitesh Choudhary (Chai aur Code) --- 📌 Series Progress Day 1 → What is JavaScript Day 2 → Variables & Data Types Day 3 → Type Conversion & Operators Day 4 → Truthy & Falsy + Comparison Operators Day 5 → If Else + Switch + Ternary Day 6 → Loops Day 7 → Break + Continue + Nested Loops Day 8 → Functions Basics Day 9 → Arrow + Default + Rest Parameters Day 10 → Callback & Higher Order Functions Day 11 → Arrays Basics Day 12 → Array Methods Day 13 → Array Iteration Day 14 → Advanced Array Methods Day 15 → Objects Basics Day 16 → Object Methods + this Day 17 → Object Destructuring Day 18 → Spread & Rest Day 19 → Advanced Objects Day 20 → DOM Introduction Day 21 → DOM Selectors Day 22 → DOM Manipulation Day 23 → Events Day 24 → Event Bubbling Day 25 → Event Delegation Day 26 → Async JavaScript Day 27 → Promises Day 28 → Async / Await Day 29 → Fetch API Day 30 → Event Loop Day 31 → Scope Day 32 → Hoisting Day 33 → Closures (Next Post) --- Follow for more 🚀 #JavaScriptSimplified #javascript #webdevelopment #coding #programming #learninpublic #100DaysOfCode #frontenddevelopment #devcommunity #codingjourney #softwaredeveloper #techcommunity #dailylearning #codeeveryday Create image based on this

🚀 JavaScript Simplified Series — Day 30 JavaScript feels fast… But have you ever wondered 👇 👉 How does it handle multiple tasks at once? 👉 How does async code run without blocking? This is where the **Event Loop** comes in 😎 --- ## 🤯 The Big Confusion JavaScript is **single-threaded** 👉 It can do **one thing at a time** Then how does this work? 👇 ```javascript id="el1" console.log("Start") setTimeout(() => { console.log("Async Task") }, 0) console.log("End") ``` 👉 Output: Start End Async Task Wait… why? 🤔 --- ## 🔥 Behind the Scenes JavaScript has 3 main parts: 👉 Call Stack 👉 Web APIs 👉 Callback Queue --- ## 🔹 Step by Step Flow 1️⃣ `console.log("Start")` → runs first 2️⃣ `setTimeout` → goes to **Web API** 3️⃣ `console.log("End")` → runs next 4️⃣ Callback goes to **Queue** 5️⃣ Event Loop checks → stack empty? 6️⃣ Yes → push callback to stack 👉 Then runs → "Async Task" --- ## 🔍 Visualization ```id="viz1" Call Stack → Executes code Web APIs → Handles async tasks Queue → Stores callbacks Event Loop → Manages everything ``` --- ## 🔥 Real Life Example Think of a **restaurant 🍽️** 👉 Waiter takes order → sends to kitchen 👉 Kitchen prepares food 👉 Meanwhile waiter serves others 👉 When food is ready → serves you 👉 Event Loop = waiter managing tasks --- ## 🔥 Simple Summary JS → single-threaded Async → handled outside Event Loop → manages execution --- ### 💡 Programming Rule **JavaScript is not multi-threaded… but it behaves like it is.** --- If you want to learn JavaScript in a **simple and practical way**, you can follow these YouTube channels: • Rohit Negi • Hitesh Choudhary (Chai aur Code) --- 📌 Series Progress Day 1 → What is JavaScript Day 2 → Variables & Data Types Day 3 → Type Conversion & Operators Day 4 → Truthy & Falsy + Comparison Operators Day 5 → If Else + Switch + Ternary Day 6 → Loops Day 7 → Break + Continue + Nested Loops Day 8 → Functions Basics Day 9 → Arrow + Default + Rest Parameters Day 10 → Callback & Higher Order Functions Day 11 → Arrays Basics Day 12 → Array Methods Day 13 → Array Iteration Day 14 → Advanced Array Methods Day 15 → Objects Basics Day 16 → Object Methods + this Day 17 → Object Destructuring Day 18 → Spread & Rest Day 19 → Advanced Objects Day 20 → DOM Introduction Day 21 → DOM Selectors Day 22 → DOM Manipulation Day 23 → Events Day 24 → Event Bubbling Day 25 → Event Delegation Day 26 → Async JavaScript Day 27 → Promises Day 28 → Async / Await Day 29 → Fetch API Day 30 → Event Loop Day 31 → Scope (Next Post) --- Follow for more 🚀 #JavaScriptSimplified #javascript #webdevelopment #coding #programming #learninpublic #100DaysOfCode #frontenddevelopment #devcommunity #codingjourney #softwaredeveloper #techcommunity #dailylearning #codeeveryday

🚀 JavaScript Simplified Series — Day 38 You type in a search bar… And API call starts firing on **every single keystroke** 😵 👉 Type “A” → API call 👉 Type “Ab” → API call 👉 Type “Abh” → API call Server overload 💥 App slow 😓 --- ## 🔥 Problem → Too many function calls --- ## 🔥 Solution → Debounce --- ## 🔹 What is Debouncing? Debouncing means: 👉 **Delay execution** 👉 Until user stops typing --- ## 🔹 Example ```javascript id="db1" function debounce(fn, delay) { let timer return function(...args) { clearTimeout(timer) timer = setTimeout(() => { fn(...args) }, delay) } } ``` --- ## 🔹 Usage ```javascript id="db2" function search(query) { console.log("Searching for:", query) } let debouncedSearch = debounce(search, 500) // call this on input event debouncedSearch("Abhay") ``` 👉 Only runs after user stops typing --- ## 🔍 What’s happening? 👉 Every new call clears previous timer 👉 Only last call executes --- ## 🔥 Real Life Example Think of a **remote button 📺** 👉 You press multiple times 👉 TV reacts only after you stop --- ## 🔥 Where is Debounce used? 👉 Search bars 🔍 👉 Resize events 👉 Input fields 👉 API calls --- ## 🔥 Simple Summary Debounce → delay execution Avoid → unnecessary calls Improve → performance --- ### 💡 Programming Rule **Don’t run code on every action. Run it at the right time.** --- If you want to learn JavaScript in a **simple and practical way**, you can follow these YouTube channels: • Rohit Negi • Hitesh Choudhary (Chai aur Code) --- 📌 Series Progress Day 1 → What is JavaScript Day 2 → Variables & Data Types Day 3 → Type Conversion & Operators Day 4 → Truthy & Falsy + Comparison Operators Day 5 → If Else + Switch + Ternary Day 6 → Loops Day 7 → Break + Continue + Nested Loops Day 8 → Functions Basics Day 9 → Arrow + Default + Rest Parameters Day 10 → Callback & Higher Order Functions Day 11 → Arrays Basics Day 12 → Array Methods Day 13 → Array Iteration Day 14 → Advanced Array Methods Day 15 → Objects Basics Day 16 → Object Methods + this Day 17 → Object Destructuring Day 18 → Spread & Rest Day 19 → Advanced Objects Day 20 → DOM Introduction Day 21 → DOM Selectors Day 22 → DOM Manipulation Day 23 → Events Day 24 → Event Bubbling Day 25 → Event Delegation Day 26 → Async JavaScript Day 27 → Promises Day 28 → Async / Await Day 29 → Fetch API Day 30 → Event Loop Day 31 → Scope Day 32 → Hoisting Day 33 → Closures Day 34 → Prototypes Day 35 → Classes Day 36 → Inheritance Day 37 → Modules Day 38 → Debounce Day 39 → Throttle (Next Post) --- Follow for more 🚀 #JavaScriptSimplified #javascript #webdevelopment #coding #programming #learninpublic #100DaysOfCode #frontenddevelopment #devcommunity #codingjourney #softwaredeveloper #techcommunity #dailylearning #codeeveryday

🚀 JavaScript Simplified Series — Day 37 Till now… you’ve written all your JavaScript in one file 😵 👉 Everything mixed together 👉 Hard to manage 👉 Hard to scale What if you could **split your code into multiple files** and still use them together? 🤔 --- ## 🔥 Solution → Modules --- ## 🔹 What are Modules? Modules allow you to: 👉 Break code into **separate files** 👉 Reuse code easily 👉 Keep code clean & organized --- ## 🔹 Exporting Code ```javascript id="md1" // math.js export function add(a, b) { return a + b } ``` 👉 `export` makes function available outside --- ## 🔹 Importing Code ```javascript id="md2" // main.js import { add } from "./math.js" console.log(add(5, 3)) ``` 👉 Output: 8 --- ## 🔹 Default Export ```javascript id="md3" // user.js export default function greet() { console.log("Hello") } ``` Import: ```javascript id="md4" import greet from "./user.js" ``` --- ## 🔥 Real Life Example Think of a big project 🏢 👉 One file → login 👉 One file → dashboard 👉 One file → API All connected… but separate --- ## 🔥 Why Modules Matter? ✅ Clean code ✅ Reusable logic ✅ Easy to maintain ✅ Scalable projects --- ## 🔥 Simple Summary export → share code import → use code modules → organize code --- ### 💡 Programming Rule **Divide your code. Organize it. Scale it.** --- If you want to learn JavaScript in a **simple and practical way**, you can follow these YouTube channels: • Rohit Negi • Hitesh Choudhary (Chai aur Code) --- 📌 Series Progress Day 1 → What is JavaScript Day 2 → Variables & Data Types Day 3 → Type Conversion & Operators Day 4 → Truthy & Falsy + Comparison Operators Day 5 → If Else + Switch + Ternary Day 6 → Loops Day 7 → Break + Continue + Nested Loops Day 8 → Functions Basics Day 9 → Arrow + Default + Rest Parameters Day 10 → Callback & Higher Order Functions Day 11 → Arrays Basics Day 12 → Array Methods Day 13 → Array Iteration Day 14 → Advanced Array Methods Day 15 → Objects Basics Day 16 → Object Methods + this Day 17 → Object Destructuring Day 18 → Spread & Rest Day 19 → Advanced Objects Day 20 → DOM Introduction Day 21 → DOM Selectors Day 22 → DOM Manipulation Day 23 → Events Day 24 → Event Bubbling Day 25 → Event Delegation Day 26 → Async JavaScript Day 27 → Promises Day 28 → Async / Await Day 29 → Fetch API Day 30 → Event Loop Day 31 → Scope Day 32 → Hoisting Day 33 → Closures Day 34 → Prototypes Day 35 → Classes Day 36 → Inheritance Day 37 → Modules Day 38 → Debounce (Next Post) --- Follow for more 🚀 #JavaScriptSimplified #javascript #webdevelopment #coding #programming #learninpublic #100DaysOfCode #frontenddevelopment #devcommunity #codingjourney #softwaredeveloper #techcommunity #dailylearning #codeeveryday

🚀 JavaScript Simplified Series — Day 26 You click a button… But nothing happens immediately 😳 Instead… it waits. Then suddenly → response comes. How does JavaScript handle this? 🤔 🔥 The Problem JavaScript runs line by line (synchronously) console.log("Start") console.log("Process") console.log("End") 👉 Output: Start Process End Everything runs one after another 😵 But Real World is Different Think about: 👉 API calls 👉 File loading 👉 Timers They take time ⏳ If JavaScript waits… everything will freeze ❌ 🔥 Solution → Asynchronous JavaScript JavaScript can handle tasks without blocking execution 🔹 Example with setTimeout console.log("Start") setTimeout(() => { console.log("Delayed Task") }, 2000) console.log("End") 👉 Output: Start End Delayed Task 🔍 What’s happening? 👉 setTimeout runs later 👉 JavaScript doesn’t wait 👉 Code continues execution 🔹 Callback in Async setTimeout(function() { console.log("Task Done") }, 1000) 👉 Function runs after delay 📌 This function is a callback 🔥 Real Life Example Ordering food 🍔 You order → wait Meanwhile → you do other work Food arrives later 👉 That’s async behavior 🔥 Simple Summary Sync → line by line execution Async → non-blocking execution Callback → function runs later 💡 Programming Rule Don’t block execution. Let JavaScript handle tasks asynchronously. If you want to learn JavaScript in a simple and practical way, you can follow these YouTube channels: • Rohit Negi • Hitesh Choudhary (Chai aur Code) 📌 Series Progress Day 1 → What is JavaScript Day 2 → Variables & Data Types Day 3 → Type Conversion & Operators Day 4 → Truthy & Falsy + Comparison Operators Day 5 → If Else + Switch + Ternary Day 6 → Loops Day 7 → Break + Continue + Nested Loops Day 8 → Functions Basics Day 9 → Arrow + Default + Rest Parameters Day 10 → Callback & Higher Order Functions Day 11 → Arrays Basics Day 12 → Array Methods Day 13 → Array Iteration Day 14 → Advanced Array Methods Day 15 → Objects Basics Day 16 → Object Methods + this Day 17 → Object Destructuring Day 18 → Spread & Rest Day 19 → Advanced Objects Day 20 → DOM Introduction Day 21 → DOM Selectors Day 22 → DOM Manipulation Day 23 → Events Day 24 → Event Bubbling Day 25 → Event Delegation Day 26 → Async JavaScript (Callbacks) Day 27 → Promises (Next Post) Follow for more 🚀 #JavaScriptSimplified #javascript #webdevelopment #coding #programming #learninpublic #100DaysOfCode #frontenddevelopment #devcommunity #codingjourney #softwaredeveloper #techcommunity #dailylearning #codeeveryday

🚀 JavaScript Simplified Series — Day 31 You wrote a variable… But suddenly 😳 👉 It works in one place 👉 But gives error in another Why? 🤔 --- ## 🔥 This is called → Scope --- ## 🔹 What is Scope? Scope defines **where a variable can be accessed** 👉 Kaha use kar sakte ho 👉 Kaha nahi --- ## 🔹 1. Global Scope ```javascript id="sc1" let name = "Abhay" function greet() { console.log(name) } greet() ``` 👉 Accessible everywhere 📌 Global = sab jagah access --- ## 🔹 2. Function Scope ```javascript id="sc2" function test() { let age = 22 console.log(age) } test() console.log(age) ❌ ``` 👉 Error ❌ 📌 Function ke bahar access nahi --- ## 🔹 3. Block Scope (let & const) ```javascript id="sc3" if (true) { let city = "Delhi" console.log(city) } console.log(city) ❌ ``` 👉 Error ❌ 📌 Block ke bahar access nahi --- ## 🔥 var vs let vs const ```javascript id="sc4" if (true) { var x = 10 } console.log(x) // works 😳 ``` 👉 `var` ignores block scope 📌 `let` & `const` follow block scope --- ## 🔥 Real Life Example Think of a house 🏠 👉 Global → pura ghar 👉 Function → ek room 👉 Block → ek drawer Har cheez har jagah access nahi hoti --- ## 🔥 Simple Summary Global → everywhere Function → inside function Block → inside {} --- ### 💡 Programming Rule **Keep variables limited. Smaller scope = fewer bugs.** --- If you want to learn JavaScript in a **simple and practical way**, you can follow these YouTube channels: • Rohit Negi • Hitesh Choudhary (Chai aur Code) --- 📌 Series Progress Day 1 → What is JavaScript Day 2 → Variables & Data Types Day 3 → Type Conversion & Operators Day 4 → Truthy & Falsy + Comparison Operators Day 5 → If Else + Switch + Ternary Day 6 → Loops Day 7 → Break + Continue + Nested Loops Day 8 → Functions Basics Day 9 → Arrow + Default + Rest Parameters Day 10 → Callback & Higher Order Functions Day 11 → Arrays Basics Day 12 → Array Methods Day 13 → Array Iteration Day 14 → Advanced Array Methods Day 15 → Objects Basics Day 16 → Object Methods + this Day 17 → Object Destructuring Day 18 → Spread & Rest Day 19 → Advanced Objects Day 20 → DOM Introduction Day 21 → DOM Selectors Day 22 → DOM Manipulation Day 23 → Events Day 24 → Event Bubbling Day 25 → Event Delegation Day 26 → Async JavaScript Day 27 → Promises Day 28 → Async / Await Day 29 → Fetch API Day 30 → Event Loop Day 31 → Scope Day 32 → Hoisting (Next Post) --- Follow for more 🚀 #JavaScriptSimplified #javascript #webdevelopment #coding #programming #learninpublic #100DaysOfCode #frontenddevelopment #devcommunity #codingjourney #softwaredeveloper #techcommunity #dailylearning #codeeveryday

POST 4 — Prototypes Are Not Legacy. They're Still Running Your Code. 🔗 Most modern JavaScript developers never think about prototypes. They use classes, they use frameworks, they move on. But prototypes are still running underneath every object you create. And not understanding them causes real bugs. Here's what you need to know 👇 ───────────────────────── What a prototype actually is: Every object in JavaScript has an internal link to another object — its prototype. When you access a property on an object and it doesn't exist on that object directly, JavaScript walks UP the prototype chain looking for it. It keeps walking until it finds the property or hits null at the top. This is called prototype delegation — and it's how inheritance works in JavaScript at the engine level. ───────────────────────── Classes are not classes: When you write a class in JavaScript, you're not creating anything like a Java or C# class. You're creating a constructor function and populating its prototype object with methods. `class Dog extends Animal` is syntactic sugar over prototype chain wiring. The prototype chain is still there. The class syntax just makes it look familiar to developers from other languages. ───────────────────────── Why this causes real bugs: If you mutate a property on a prototype — not an instance, the PROTOTYPE — every single object that inherits from it sees the change. This is one of the oldest and most dangerous JavaScript bugs. It shows up in legacy codebases, in poorly written polyfills, and in careless use of Object.prototype. ───────────────────────── The performance angle: Property lookup walks the prototype chain on every access. Deep inheritance hierarchies mean longer chains and slower lookups. Prefer shallow chains. Prefer composition over deep inheritance. Your CPU will thank you. ───────────────────────── What modern JS got right: Object.create(null) creates an object with NO prototype at all. This is useful for pure dictionary objects where you never want accidental prototype property collisions. A great pattern for cache objects, lookup tables, and any object where you're using dynamic string keys. ───────────────────────── The one thing to remember: There are no classes in JavaScript at the engine level. There are only objects, functions, and prototype chains. Everything else is syntax. ───────────────────────── Did understanding prototypes change how you write JavaScript? Share your experience below 👇 #JavaScript #WebDevelopment #Programming #FrontendDevelopment #WebDev

Most JavaScript devs think Object keys follow insertion order. And it’s caught even senior devs off guard. Create an object and add keys in this order: "b", "a", "1". const obj = {}; obj.b = 'second'; obj.a = 'third'; obj.1 = 'first'; Log Object.keys(obj). You’d expect: ['b', 'a', '1'] You get: ['1', 'b', 'a'] 🤯 The number jumped to the front, but the strings stayed in order. Same object. Same assignment logic. Completely unexpected order. This silently breaks: → API wrappers that expect keys to match a specific schema → UI components that map over objects for "alphabetical" sorting → Testing suites that compare object snapshots No error thrown. Just a data structure that "rearranges" itself. Why does this happen? It’s defined in the ECMAScript spec (OrdinaryOwnPropertyKeys).  JavaScript objects don't have a single "order." They follow a strict three-tier hierarchy: 1. Integer Indices: Sorted in ascending numeric order (always first). 2. String Keys: Sorted in chronological insertion order. 3. Symbol Keys: Sorted in chronological insertion order (always last). The engine treats "1" as an integer index, so it "cuts the line" and moves to the very front, regardless of when you added it. Once you know this, you'll stop trusting Object.keys() for ordered data and start reaching for Map. 🔖 Learn more about how JS engines handle property order → https://lnkd.in/gRY6hdcM Were you aware that numbers always "cut the line" in JS objects? 1️⃣ Yes / 2️⃣ No 👇 #JavaScript #WebDev #Coding #SoftwareEngineering #Frontend