ReactJS Full Course for Beginners 📘

Welcome to the first episode of the only React JS course you'll ever need. If you've mastered HTML, CSS, and JavaScript but are tired of tutorials that just show you the 'how' without the 'why', you're in the right place. We're throwing out memorization and building a deep, fundamental understanding of React from First Principles.

In this first video, we go back to the beginning. Before we write a single line of JSX, we explore the core problem React was created to solve. We'll compare the old, imperative way of building web apps with React's powerful declarative model, solidifying the one concept that rules them all: UI = f(state).

✨ IN THIS VIDEO, YOU WILL LEARN:
(Using timestamps helps with SEO and user experience)

The Problem with Modern Web Apps
The "Old Way": Manual DOM Manipulation (Imperative)
The Core Flaw: Why Imperative UI is Prone to Bugs
React's Big Idea: The Declarative Mindset Shift
The Golden Rule: UI = f(state) Explained
The Bedrock: React.createElement (NO JSX!)
First Principles: Why React and ReactDOM are Separate Libraries
What's Coming Next in Episode 2 (Components & JSX)

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🧠 OUR METHODOLOGY (FIRST PRINCIPLES):

Instead of memorizing a list of React features, we will build our knowledge from the ground up. Each new concept will be connected to a core truth about managing UI complexity. This method ensures you don't just know how to write React code—you'll know how to THINK in React.

✅ WHO IS THIS FOR?
- Developers who have mastered HTML, CSS, and vanilla JavaScript.
- Learners who want to understand the "why" behind the code.
- Anyone who has tried other React tutorials and felt like they were just copying and pasting.

0:00 Introduction to React
1:50 What is React
3:17 Problem 1: Creating Elements with Raw DOM
6:36 Problem 2: Repetitive Code Issues
8:33 Solution: Designing a Reusable createElement Function
11:44 Implementing Custom createElement
16:33 Handling Nested Styles (Object.assign)
22:15 What React Really Is
25:59 What ReactDOM Does
40:20 React vs ReactDOM
45:39 Why They’re Separate (Native, PDF, etc.)
53:12 Building a Custom ReactDOM Renderer
1:03:59 React 18 Rendering (createRoot)
1:06:10 Conclusion – Why JSX Matters


#ReactJS #LearnReact #ReactTutorial #WebDevelopment #JavaScript #FirstPrinciples #ReactForBeginners





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