[PART I GETTING STARTED]

CHAPTER 1 JavaScript
_1.1 About the book
_1.2 Origin of JavaScript Name
_1.3 Specification
_1.4 The many faces of JS
_1.5 Backward and Forward Compatibility
_1.6 Understanding the Interpreter
_1.7 strict mode
_1.8 Summary

CHAPTER 2: A Look at JavaScript
_2.1 file is a program
_2.2 value
_2.3 Variable declaration and use
_2.4 Function
_2.5 comparison
_2.6 Code Structuring Patterns
_2.7 Down a deeper rabbit hole

CHAPTER 3: Uncovering JavaScript's Roots
_3.1 Iteration
_3.2 Closure
_3.3 this keyword
_3.4 Prototype
_3.5 Asking 'Why?'

CHAPTER 4 THE BIGGER PICTURE
_4.1 First Pillar: Scope and Closures
_4.2 Second Pillar: Prototype
_4.3 Third Pillar: Types and Type Coercion
_4.4 Following the essence of JS
_4.5 Learning Order

APPENDIX A Going Further
_A.1 value vs.
reference
_A.2 Various types of functions
_A.3 Forced Conditional Comparison
_A.4 Prototype Class

APPENDIX B Practice is the only way!
_B.1 Practice Comparison
_B.2 Practice Closure
_B.3 Practicing Prototyping
_B.4 Model Answer

[PART II Scope and Closure]

CHAPTER 1 Scope
_1.1 About the book
_1.2 Compile vs.
Interpret
_1.3 Compile the code
_1.4 Compiler itself
_1.5 Changing scope at runtime
_1.6 Lexical Scope

CHAPTER 2 Lexical Scope
_2.1 Beads and Buckets
_2.2 Dialogue between JS engine members
_2.3 Nested scopes
_2.4 Summary

CHAPTER 3 Scope Chain
_3.1 The Truth of Exploration
_3.2 Variable Shadowing
_3.3 Function Name Scope
_3.4 Arrow functions
_3.5 Summary

CHAPTER 4 Global Scope
_4.1 Why you should learn global scope
_4.2 Location of global scope
_4.3 globalThis
_4.4 Summary

CHAPTER 5: The Secret Life Cycle of Variables
_5.1 When variables can be used
_5.2 Hoisting: Just a metaphor
_5.3 Handling duplicate declarations
_5.4 Uninitialized Variables and TDZ
_5.5 Summary

CHAPTER 6 Scope Exposure Limits
_6.1 Principle of Minimum Exposure (POLE)
_6.2 Hiding in general (function) scope
_6.3 Scope with blocks
_6.4 Declaring functions within blocks
_6.5 Summary

CHAPTER 7: USING CLOSURES
_7.1 Observing closures
_7.2 Closure Lifecycle and Garbage Collection
_7.3 Another perspective
_7.4 Why Use Closures?
_7.5 Summary

CHAPTER 8 MODULE PATTERN
_8.1 Encapsulation and Principle of Minimum Exposure (POLE)
_8.2 What is a module?
_8.3 CommonJS modules in Node.js
_8.4 Latest ES module
_8.5 Summary

APPENDIX A One Step Further
_A.1 Implicit Scope
_A.2 Anonymous functions vs.
Named functions
_A.3 Hoisting: Functions and Variables
_A.4 Argument for var
_A.5 TDZ
_A.6 Are synchronous callbacks still closures?
_A.7 Classic module variant

APPENDIX B Practice Problems
_B.1 Beads and Buckets
_B.2 Closure 1
_B.3 Closure 2
_B.4 Closure 3
_B.5 Module
_B.6 Model Answer

JavaScript is as visible as you know, so understand it more deeply.

Many people have learned JavaScript, but far fewer have mastered it completely.
Don't you think you know everything, but in reality, there are concepts you've been using out of habit? Is it really true that you know everything about JavaScript? In his "You Don't Know JS Yet" series, author Kyle Simpson delves into obscure JavaScript concepts, common misconceptions, and difficult-to-understand areas.
It helps you understand JavaScript much more deeply by going over confusing or overlooked parts.
As you delve into the world of JavaScript explained in this book, you'll naturally learn how JavaScript works and its design principles, and you'll also be able to establish the mindset and perspective you need as a developer.


* This book is a compilation of the first volume of the 『You Don't Know JS Yet』 series, "Getting Started" and the second volume, "Scope and Closures," into a single paperback. Part 1 covers the contents of Volume 1, and Part 2 covers the contents of Volume 2.

Key Contents

● Getting started with Part 1
○ The evolution of JavaScript
○ How the program actually works
○ Correcting common misconceptions
○ Introduction to basic components, types, closures, and prototypes
● Part 2 Scope and Closure
○ Limiting the scope exposure of variables by nesting lexical scopes
○ Let's look at a function that remembers variables through closures.
○ Introduction to modules, the most important code organization pattern in programming

Target audience

● JavaScript developers who want to level up from beginner to intermediate/advanced
● Developers who have experience developing JavaScript but sometimes get confused about the concepts
Developers struggling with unknown JavaScript errors

Recommended reviews

This is a great book to get you started in the world of JavaScript.
We'll explain all the concepts related to JavaScript, plus some of its secrets and tricks that can easily trip you up.
I recommend this book to developers who want to gain a solid understanding of the world of JavaScript!
- Lily Rojo, Amazon reader

The 『You Don't Know JS Yet』 series brings the joy of learning JavaScript.
It shows the big picture of JavaScript without missing the key points.
The author's concise, comprehensive, and penetrating style and philosophy will expand your thinking.
I hope the other series comes out soon.
- Rabi Abraham, Amazon Reader

Thanks to this book, I finally understood JavaScript.
It's full of detailed, easy-to-understand content that will help even competent developers.
A must-read for JavaScript developers!
- Nile, Amazon Reader