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SKILL JOURNEY

JavaScript

The language of the web

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CHAPTER 01
Foundations
Lay the groundwork
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1YOU ARE HERE
Lesson 1+50 XP
Hello, World
Print a greeting.
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2
Lesson 2+30 XP
Comments
Notes for humans.
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Lesson 3+60 XP
Const
Immutable binding.
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Lesson 4+50 XP
Let
Reassignable binding.
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Lesson 5+50 XP
String
Quotes are flexible.
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CHAPTER 02
Core Concepts
Build the core skills
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Lesson 6+70 XP
Template Literal
Backtick interpolation.
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Lesson 7+60 XP
Numbers
Math basics.
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Lesson 8+50 XP
Boolean
True or false.
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Lesson 9+70 XP
If Statement
Branching.
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Lesson 10+80 XP
If / Else
Two branches.
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CHAPTER 03
Building Blocks
Wire things together
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Lesson 11+80 XP
Ternary
Inline conditional.
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Lesson 12+90 XP
Function
Reusable code.
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Lesson 13+90 XP
Arrow Function
Concise functions.
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Lesson 14+60 XP
Array
Lists of values.
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Lesson 15+70 XP
Array.push
Add an item.
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CHAPTER 04
Advanced Patterns
Level up your craft
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Lesson 16+100 XP
For Loop
Classic loop.
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Lesson 17+90 XP
For...Of
Iterate values.
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Lesson 18+100 XP
Array.map
Transform each.
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Lesson 19+110 XP
Array.filter
Keep matches.
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Lesson 20+140 XP
Array.reduce
Fold to one value.
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CHAPTER 05
Mastery
Master the language
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Lesson 21+80 XP
Object Literal
Key-value pairs.
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Lesson 22+100 XP
Destructuring
Pull out fields.
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Lesson 23+100 XP
Spread
Expand an array.
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Lesson 24+130 XP
Async Function
Async / await.
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Lesson 25+120 XP
Promise
Then chain.
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CHAPTER 06
Deep Dive
Go beneath the surface
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Lesson 26+130 XP
Class
OOP in JS.
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Lesson 27+80 XP
Export
Share code between files.
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Lesson 28+90 XP
Set
Unique values collection.
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Lesson 29+90 XP
Map Object
Key-value with any keys.
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Lesson 30+110 XP
Optional Chaining
Safe navigation.
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CHAPTER 07
Pro Skills
Ship like a pro
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Lesson 31+100 XP
Nullish Coalescing
Default for null/undefined.
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Lesson 32+130 XP
Rest Parameters
Collect into an array.
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Lesson 33+130 XP
Try / Catch
Catch runtime errors.
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Lesson 34+110 XP
JSON Parse
Parse a JSON string.
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35
Lesson 35+140 XP
Fetch API
Make a network request.
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JavaScript Master
35 lessons left to claim the crown