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Showing posts from October, 2025

๐Ÿง  What is Stack, Heap Memory, and String Pool in Java?

If you’ve started learning Java, you’ve probably heard people say things like: “That variable is stored on the stack,” or “The object lives in the heap.” And then there’s something called the String Pool — sounds confusing, right? Don’t worry ๐Ÿ˜„ — this post will make everything super simple to understand. ๐Ÿงฉ Let’s start with: What happens when you run a Java program? When your Java code runs, the JVM (Java Virtual Machine) divides memory into different sections . The two most important ones are: Stack Memory Heap Memory Let’s see what each one does ๐Ÿ‘‡ ๐Ÿฅž 1. Stack Memory — for short-term data Think of Stack Memory as a temporary notebook ๐Ÿ“’ that the JVM uses to store small, short-lived data. ✳️ Used for: Primitive variables ( int , char , boolean , etc.) References to objects (not the objects themselves) Method calls and local variables Every time a method is called, the JVM creates a stack frame for it. When the method finishes, its frame is r...

๐Ÿงฉ What is JIT vs AOT in Angular?

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 Perfect ๐Ÿ‘ Let’s write a simple, beginner-friendly blog post on “JIT vs AOT in Angular” — written in a style that’s easy for students or new developers to understand. You can directly post this to your Blogger or use it in your YouTube video description . ๐Ÿงฉ What is JIT vs AOT in Angular? (Beginner Friendly Explanation) When you create an Angular app, it doesn’t run directly in the browser just as you wrote it. Angular has to convert your TypeScript and HTML templates into plain JavaScript that browsers understand. This conversion process is called compilation — and Angular provides two ways to do it: ๐Ÿ‘‰ Just-in-Time (JIT) and ๐Ÿ‘‰ Ahead-of-Time (AOT) . Let’s understand both in a simple way ๐Ÿ‘‡ ⚙️ 1️⃣ What is JIT (Just-in-Time) Compilation? JIT means “compile your app when it runs.” That is, when you open your app in the browser, Angular will compile the templates and TypeScript code at runtime (on the fly) before showing anything on screen. ๐Ÿง  Think of it like c...

AngularJS vs Angular (Angular 2+)

๐Ÿงฉ 1. Architecture Feature AngularJS (v1.x) Angular (v2+) Pattern MVC (Model-View-Controller) Component-based architecture Main Building Block Controllers, Scope, Directives Components, Modules, Services Data Binding Two-way data binding One-way and two-way data binding (more controlled) ⚙️ 2. Language Feature AngularJS Angular Language Used JavaScript (ES5) TypeScript (superset of JavaScript) Type Safety No static typing Strongly typed with TypeScript ⚡ 3. Performance Feature AngularJS Angular Speed Slower due to digest cycle and watchers Faster due to improved change detection and Ahead-of-Time (AOT) compilation Mobile Support Poor Designed with mobile support in mind ๐Ÿง  4. Dependency Injection Feature AngularJS Angular DI Implementation Limited and less flexible Fully-fledged, hierarchical dependency injection system ๐ŸŽจ 5. UI & Templates Feature AngularJS Angular Templates Wri...

⚡ What Is Hoisting in JavaScript?

⚡ What Is Hoisting in JavaScript? Hoisting means that JavaScript moves variable and function declarations to the top of their scope (before code execution) — but not the initialization . So JavaScript “knows” about your variables and functions before it runs your code, but values are not yet assigned. ๐Ÿง  Example 1 — Variable Hoisting (with var ) console.log(a); // ๐Ÿ‘‰ undefined var a = 10; ๐Ÿ” Behind the Scenes JavaScript internally does this: var a; // Declaration is hoisted console.log(a); a = 10; // Initialization stays in place ✅ So it doesn’t throw an error — it just logs undefined . ๐Ÿšซ let and const Are Not Fully Hoisted console.log(b); // ❌ ReferenceError: Cannot access 'b' before initialization let b = 20; ✅ Explanation: let and const are hoisted , but they are not initialized until the execution reaches that line. The time between hoisting and initialization is called the Temporal Dead Zone (TDZ) . ๐Ÿงฉ Example 2 — Function Hoi...

๐Ÿงต JavaScript Interview Prep: Single-Threaded or Multi-Threaded? Event Loop? Async Tasks?

If you’re preparing for a JavaScript interview , chances are you’ll come across questions like: Is JavaScript single-threaded or multi-threaded? How does JavaScript handle asynchronous tasks? What is the event loop, and how does it work? These are fundamental concepts that every JavaScript developer should understand — not only for interviews but also for writing efficient, non-blocking code. Let’s break them down clearly ๐Ÿ‘‡ ๐Ÿง  Question 1: Is JavaScript Single-Threaded or Multi-Threaded? The short answer is: ๐Ÿ‘‰ JavaScript is single-threaded. That means it can execute only one task at a time on a single main thread . This single thread handles: Code execution Function calls Event handling DOM updates (in browsers) So, when you run JavaScript, it processes your code line by line , synchronously . If one piece of code takes too long to finish, the rest of the program must wait — this is called blocking . ⚙️ Question 2: How Does JavaScript Handle Asynchronous Task...