PLAINFINCH
learn by building
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Lessons
HTML
CSS
JS
SQL
Git
AI
Servers
Access
Tests
Speed
Foundations
How JavaScript works
The console
Variables
Values and types
Operators
Working with text
Logic
Making decisions
Loops
Functions
Scope
Errors
Data
Arrays
Array methods
Objects
Sets and Maps
JSON
Patterns with regular expressions
Numbers and dates
The page
Finding elements
Changing content
Classes and styles
Creating elements
Events
Forms
Event delegation
Milestone: a quiz
Waiting for things
Timers
Promises
async and await
Fetching data
Organising code
Modules
Classes
Storage
Keeping the page in sync
Milestone: a to-do app
Quality
Debugging JavaScript
Accessible interactivity
Showing user text safely
Reading AI-generated code
Project
Project: bring your profile to life
Tools
Explain my HTML
Playground
Every HTML element
Every CSS property
Everyday JavaScript
Every SQL keyword
Every Git command
AI review checklist
Every server term
Accessibility checklist
Every testing term
Every performance term
How HTML becomes a page
Playground
A blank page with HTML, CSS and JavaScript editors, a live preview and a console.