All courses

49 courses. Every one finishable in an afternoon.

49 courses
00
HTML basics
88 min read·8 lessons

HTML basics

The language the web is written in.

21
Semantic HTML
122 min read·8 lessons

Semantic HTML

Landmarks, headings, and the elements browsers ship for free.

22
HTML forms
138 min read·9 lessons

HTML forms

Inputs, validation, dialogs — forms the browser does most of for you.

23
HTML media
104 min read·7 lessons

HTML media

Images, video, audio, tracks — the responsive media story.

24
HTML document and meta
115 min read·8 lessons

HTML document and meta

The head decides how the page is shared, found, and loaded.

03
CSS fundamentals
130 min read·8 lessons

CSS fundamentals

The cascade, the box, and the parts you can't skip.

Aa
10
CSS styling essentials
135 min read·9 lessons·

CSS styling essentials

type, color, shadow — the layer that makes a page feel made.

01
CSS Flexbox
95 min read·8 lessons·

CSS Flexbox

One-dimensional layout, demystified.

02
CSS Grid
110 min read·9 lessons·

CSS Grid

Two dimensions when one is not enough.

04
Responsive design
130 min read·8 lessons·

Responsive design

one layout that fits every screen.

08
CSS animations
110 min read·7 lessons·

CSS animations

motion that doesn't get in the way.

09
Modern CSS
120 min read·8 lessons·

Modern CSS

the features that changed how stylesheets are written.

JS
07
JavaScript Foundations
140 min read·8 lessons·

JavaScript Foundations

Values, scope, and the parts that decide everything else.

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05
JavaScript Functions
120 min read·9 lessons·

JavaScript Functions

Closures, hoisting, this — finally clear.

11
Objects & Classes
125 min read·8 lessons·

Objects & Classes

Objects, prototypes, classes — one chain, three ways to spell it.

12
Iteration & Collections
130 min read·9 lessons·

Iteration & Collections

The vocabulary you reach for on every other line.

13
Text & Data
125 min read·8 lessons·

Text & Data

Regex, JSON, dates, money — shaping the things a UI shows.

06
Promises & async
100 min read·7 lessons·

Promises & async

Microtasks, macrotasks, and you.

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17
Modern JavaScript
100 min read·7 lessons·

Modern JavaScript

The features that changed how scripts are written.

18
Forms in depth
170 min read·11 lessons

Forms in depth

State, validation, and the UX you actually want.

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07
TypeScript essentials
160 min read·11 lessons

TypeScript essentials

Types that catch what tests miss.

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22
TypeScript config and tooling
115 min read·8 lessons·

TypeScript config and tooling

The compiler, the config, and where types come from.

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23
TypeScript design patterns
125 min read·8 lessons·

TypeScript design patterns

Modeling domains so wrong states don't compile.

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24
TypeScript and the runtime
110 min read·7 lessons

TypeScript and the runtime

Schema validation, type guards, the boundary where TypeScript stops.

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25
TypeScript advanced types
135 min read·8 lessons

TypeScript advanced types

Conditional, mapped, template literal — the type system as a language.

26
React Foundations
140 min read·9 lessons·

React Foundations

Components, JSX, and what "render" actually means.

27
React State & Events
120 min read·8 lessons·

React State & Events

useState, events, forms — the day-one productive surface.

28
React Effects
110 min read·8 lessons·

React Effects

useEffect, cleanup, and the cases you don't need it.

29
React Hooks In Depth
132 min read·9 lessons·

React Hooks In Depth

useReducer, context, refs, memoization, custom hooks.

30
React Forms & Actions
120 min read·8 lessons·

React Forms & Actions

Actions, useActionState, useOptimistic — forms in React 19.

31
React Suspense & Transitions
115 min read·8 lessons·

React Suspense & Transitions

<Suspense>, use(), transitions — loading as a primitive.

32
React Server Components
145 min read·9 lessons·

React Server Components

The server/client boundary, server actions, streaming.

33
React Performance
125 min read·8 lessons·

React Performance

Re-renders, memoization, the Profiler, code splitting.

34
React Testing
110 min read·8 lessons·

React Testing

Testing Library, userEvent, async UI, what to mock.

25
DOM and events
144 min read·10 lessons

DOM and events

The browser API the language was built to drive.

15
Web Platform APIs
155 min read·10 lessons·

Web Platform APIs

Networking, storage, workers — the rest of the browser.

16
Browser storage
140 min read·10 lessons

Browser storage

Cookies, localStorage, IndexedDB — and when each fits.

17
Service workers & PWAs
165 min read·11 lessons

Service workers & PWAs

Offline-capable web apps without the magic.

18
Web Workers
130 min read·10 lessons

Web Workers

Off the main thread, on purpose.

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10
Modules & bundlers
175 min read·12 lessons

Modules & bundlers

ESM, CJS, package.json, and what bundlers actually do.

01
Accessibility Foundations
125 min read·8 lessons·

Accessibility Foundations

who, why, and the rules the web is judged by.

02
Keyboard and Focus
115 min read·7 lessons·

Keyboard and Focus

The half of your UI that isn't a mouse.

03
ARIA in Practice
130 min read·8 lessons·

ARIA in Practice

When ARIA helps, when it hurts, and the patterns that work.

04
Accessible forms and dynamic UI
130 min read·8 lessons·

Accessible forms and dynamic UI

Errors, dialogs, route changes — the parts that break first.

05
Accessibility Testing & Process
115 min read·8 lessons·

Accessibility Testing & Process

Tools, audits, and putting a11y in your pipeline.

25
Performance and debugging
113 min read·8 lessons

Performance and debugging

Devtools, profiles, and the patterns that fix jank.

03
REST APIs
140 min read·10 lessons

REST APIs

Conventions, verbs, and graceful failure.

08
HTTP, end to end
130 min read·10 lessons

HTTP, end to end

Status codes, headers, caching.

04
Git fundamentals
180 min read·12 lessons

Git fundamentals

From commits to rebases, end to end.