Core JavaScript
Language basics: values, control flow, strings, dates, functions, objects and arrays.
Start here
Platform under construction
JavaScript course
JavaScript turns pages into applications.
This course is being structured as a complete JavaScript learning path: language fundamentals, browser interaction, async code, modern APIs, security, performance, testing and real projects.
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Course structure
The JavaScript course map is ready.
Every topic has its own URL, metadata, navigation position and full lesson route. The module now covers the language, the browser, production work and practice projects in one consistent path.
Recommended route
Four milestones make the full JavaScript path easier to follow.
You can study every lesson in order, but the course is also built as a route from language basics to browser behavior, professional production work and real projects.
Browser JavaScript
DOM, events, forms, async work and browser APIs that turn pages into interfaces.
Start hereProfessional JavaScript
Modules, debugging, security, performance, testing, tooling and production habits.
Start hereProjects
Small projects with acceptance criteria so knowledge turns into working features.
Start hereChoose your path
Not every builder needs all 173 lessons in the same order.
Use these routes when you are learning for a specific goal. The full course remains the strongest route, but these paths help entrepreneurs, designers and working developers get useful value faster.
Builder route
For entrepreneurs and makers who want to understand enough JavaScript to ship useful features.
Language route
For developers who want the core language model before touching the browser too much.
Production route
For people who already write JavaScript and want safer, cleaner release-ready work.
JavaScript Basics
Start with the language before writing clever code.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you explain what JavaScript adds on top of HTML and CSS, and where scripts should live in a real page?
JavaScript Introduction
A focused JavaScript lesson about JavaScript Introduction, with examples, common mistakes, self-checks and practical browser context.
Open lessonECMAScript
A focused JavaScript lesson about ECMAScript, with examples, common mistakes, self-checks and practical browser context.
Open lessonWhere to Place JavaScript
A focused JavaScript lesson about Where to Place JavaScript, with examples, common mistakes, self-checks and practical browser context.
Open lessonJavaScript Output
A focused JavaScript lesson about JavaScript Output, with examples, common mistakes, self-checks and practical browser context.
Open lessonConsole
A focused JavaScript lesson about Console, with examples, common mistakes, self-checks and practical browser context.
Open lessonJavaScript Syntax
A focused JavaScript lesson about JavaScript Syntax, with examples, common mistakes, self-checks and practical browser context.
Open lessonStatements
A focused JavaScript lesson about Statements, with examples, common mistakes, self-checks and practical browser context.
Open lessonComments
A focused JavaScript lesson about Comments, with examples, common mistakes, self-checks and practical browser context.
Open lessonVersions & Runtimes
Understand where JavaScript comes from and where it runs.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you tell the difference between ECMAScript, a browser API and a runtime such as Node.js?
JavaScript Versions
A focused JavaScript lesson about JavaScript Versions, with examples, common mistakes, self-checks and practical browser context.
Open lessonTC39 Process
A focused JavaScript lesson about TC39 Process, with examples, common mistakes, self-checks and practical browser context.
Open lessonBrowser Support
A focused JavaScript lesson about Browser Support, with examples, common mistakes, self-checks and practical browser context.
Open lessonPolyfills & Transpiling
A focused JavaScript lesson about Polyfills & Transpiling, with examples, common mistakes, self-checks and practical browser context.
Open lessonBrowser, Node, Deno & Bun
A focused JavaScript lesson about Browser, Node, Deno & Bun, with examples, common mistakes, self-checks and practical browser context.
Open lessonValues & Types
Learn what values are before moving them around.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you predict how null, undefined, truthy, falsy and converted values behave in small examples?
var, let & const
A focused JavaScript lesson about var, let & const, with examples, common mistakes, self-checks and practical browser context.
Open lessonPrimitive Types
A focused JavaScript lesson about Primitive Types, with examples, common mistakes, self-checks and practical browser context.
Open lessonObjects vs Primitives
A focused JavaScript lesson about Objects vs Primitives, with examples, common mistakes, self-checks and practical browser context.
Open lessontypeof
A focused JavaScript lesson about typeof, with examples, common mistakes, self-checks and practical browser context.
Open lessonnull & undefined
A focused JavaScript lesson about null & undefined, with examples, common mistakes, self-checks and practical browser context.
Open lessonTruthy & Falsy
A focused JavaScript lesson about Truthy & Falsy, with examples, common mistakes, self-checks and practical browser context.
Open lessonType Conversion
A focused JavaScript lesson about Type Conversion, with examples, common mistakes, self-checks and practical browser context.
Open lessonSymbol & BigInt
A focused JavaScript lesson about Symbol & BigInt, with examples, common mistakes, self-checks and practical browser context.
Open lessonOperators & Expressions
Write expressions that are clear, predictable and readable.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you use operators to make code clearer without hiding business logic in clever expressions?
Arithmetic Operators
A focused JavaScript lesson about Arithmetic Operators, with examples, common mistakes, self-checks and practical browser context.
Open lessonAssignment Operators
A focused JavaScript lesson about Assignment Operators, with examples, common mistakes, self-checks and practical browser context.
Open lessonComparison Operators
A focused JavaScript lesson about Comparison Operators, with examples, common mistakes, self-checks and practical browser context.
Open lessonLogical Operators
A focused JavaScript lesson about Logical Operators, with examples, common mistakes, self-checks and practical browser context.
Open lessonNullish & Optional Chaining
A focused JavaScript lesson about Nullish & Optional Chaining, with examples, common mistakes, self-checks and practical browser context.
Open lessonTernary Operator
A focused JavaScript lesson about Ternary Operator, with examples, common mistakes, self-checks and practical browser context.
Open lessonOperator Precedence
A focused JavaScript lesson about Operator Precedence, with examples, common mistakes, self-checks and practical browser context.
Open lessonControl Flow
Teach your code to choose paths and repeat work.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you turn decisions and loops into readable paths with guard clauses, switches and clear exits?
if, else & else if
A focused JavaScript lesson about if, else & else if, with examples, common mistakes, self-checks and practical browser context.
Open lessonswitch
A focused JavaScript lesson about switch, with examples, common mistakes, self-checks and practical browser context.
Open lessonfor Loops
A focused JavaScript lesson about for Loops, with examples, common mistakes, self-checks and practical browser context.
Open lessonwhile & do while
A focused JavaScript lesson about while & do while, with examples, common mistakes, self-checks and practical browser context.
Open lessonfor in & for of
A focused JavaScript lesson about for in & for of, with examples, common mistakes, self-checks and practical browser context.
Open lessonbreak & continue
A focused JavaScript lesson about break & continue, with examples, common mistakes, self-checks and practical browser context.
Open lessonStrings, Numbers & Math
Handle text, calculations and numeric edge cases correctly.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you format text and numbers while avoiding precision, parsing and unsafe-output mistakes?
Strings
A focused JavaScript lesson about Strings, with examples, common mistakes, self-checks and practical browser context.
Open lessonTemplate Literals
A focused JavaScript lesson about Template Literals, with examples, common mistakes, self-checks and practical browser context.
Open lessonString Methods
A focused JavaScript lesson about String Methods, with examples, common mistakes, self-checks and practical browser context.
Open lessonNumbers
A focused JavaScript lesson about Numbers, with examples, common mistakes, self-checks and practical browser context.
Open lessonNumber Methods
A focused JavaScript lesson about Number Methods, with examples, common mistakes, self-checks and practical browser context.
Open lessonMath
A focused JavaScript lesson about Math, with examples, common mistakes, self-checks and practical browser context.
Open lessonPrecision & Random Values
A focused JavaScript lesson about Precision & Random Values, with examples, common mistakes, self-checks and practical browser context.
Open lessonDates, Time & Intl
Treat dates, time zones and formatting with respect.
This chapter includes Date, Intl and Temporal, because modern JavaScript date/time work deserves more than a quick Date example.
Chapter checkpoint
Can you explain why time zones, locale formatting and Temporal need a support policy?
Date
A focused JavaScript lesson about Date, with examples, common mistakes, self-checks and practical browser context.
Open lessonDate Formats
A focused JavaScript lesson about Date Formats, with examples, common mistakes, self-checks and practical browser context.
Open lessonDate Get & Set
A focused JavaScript lesson about Date Get & Set, with examples, common mistakes, self-checks and practical browser context.
Open lessonTime Zones
A focused JavaScript lesson about Time Zones, with examples, common mistakes, self-checks and practical browser context.
Open lessonIntl
A focused JavaScript lesson about Intl, with examples, common mistakes, self-checks and practical browser context.
Open lessonTemporal
A focused JavaScript lesson about Temporal, with examples, common mistakes, self-checks and practical browser context.
Open lessonTemporal vs Date
A focused JavaScript lesson about Temporal vs Date, with examples, common mistakes, self-checks and practical browser context.
Open lessonFunctions & Scope
Make logic reusable without losing track of scope.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you explain scope, closures, callbacks and this without guessing from syntax alone?
Function Declarations
A focused JavaScript lesson about Function Declarations, with examples, common mistakes, self-checks and practical browser context.
Open lessonFunction Expressions
A focused JavaScript lesson about Function Expressions, with examples, common mistakes, self-checks and practical browser context.
Open lessonArrow Functions
A focused JavaScript lesson about Arrow Functions, with examples, common mistakes, self-checks and practical browser context.
Open lessonParameters & Arguments
A focused JavaScript lesson about Parameters & Arguments, with examples, common mistakes, self-checks and practical browser context.
Open lessonReturn Values
A focused JavaScript lesson about Return Values, with examples, common mistakes, self-checks and practical browser context.
Open lessonCallbacks
A focused JavaScript lesson about Callbacks, with examples, common mistakes, self-checks and practical browser context.
Open lessonClosures
A focused JavaScript lesson about Closures, with examples, common mistakes, self-checks and practical browser context.
Open lessonthis, call, apply & bind
A focused JavaScript lesson about this, call, apply & bind, with examples, common mistakes, self-checks and practical browser context.
Open lessonObjects, Prototypes & Classes
Understand the object model behind JavaScript.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you choose between plain objects, factory functions and classes for a small feature?
Objects
A focused JavaScript lesson about Objects, with examples, common mistakes, self-checks and practical browser context.
Open lessonProperties & Methods
A focused JavaScript lesson about Properties & Methods, with examples, common mistakes, self-checks and practical browser context.
Open lessonConstructors
A focused JavaScript lesson about Constructors, with examples, common mistakes, self-checks and practical browser context.
Open lessonPrototypes
A focused JavaScript lesson about Prototypes, with examples, common mistakes, self-checks and practical browser context.
Open lessonGetters & Setters
A focused JavaScript lesson about Getters & Setters, with examples, common mistakes, self-checks and practical browser context.
Open lessonObject Management
A focused JavaScript lesson about Object Management, with examples, common mistakes, self-checks and practical browser context.
Open lessonClasses
A focused JavaScript lesson about Classes, with examples, common mistakes, self-checks and practical browser context.
Open lessonClass Inheritance
A focused JavaScript lesson about Class Inheritance, with examples, common mistakes, self-checks and practical browser context.
Open lessonArrays & Collections
Work with lists, sets and keyed data structures.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you transform, search, sort and aggregate data without mutating state accidentally?
Arrays
A focused JavaScript lesson about Arrays, with examples, common mistakes, self-checks and practical browser context.
Open lessonArray Methods
A focused JavaScript lesson about Array Methods, with examples, common mistakes, self-checks and practical browser context.
Open lessonArray Search & Sort
A focused JavaScript lesson about Array Search & Sort, with examples, common mistakes, self-checks and practical browser context.
Open lessonArray Iteration
A focused JavaScript lesson about Array Iteration, with examples, common mistakes, self-checks and practical browser context.
Open lessonmap, filter & reduce
A focused JavaScript lesson about map, filter & reduce, with examples, common mistakes, self-checks and practical browser context.
Open lessonDestructuring
A focused JavaScript lesson about Destructuring, with examples, common mistakes, self-checks and practical browser context.
Open lessonSet & WeakSet
A focused JavaScript lesson about Set & WeakSet, with examples, common mistakes, self-checks and practical browser context.
Open lessonMap & WeakMap
A focused JavaScript lesson about Map & WeakMap, with examples, common mistakes, self-checks and practical browser context.
Open lessonJSON & Structured Data
Move data between forms, APIs and browser objects.
This chapter connects JavaScript values to the formats and browser objects used by APIs, uploads, streams and binary data.
Chapter checkpoint
Can you parse, validate and send structured data without trusting external input blindly?
JSON
A focused JavaScript lesson about JSON, with examples, common mistakes, self-checks and practical browser context.
Open lessonJSON Parse & Stringify
A focused JavaScript lesson about JSON Parse & Stringify, with examples, common mistakes, self-checks and practical browser context.
Open lessonURL & URLSearchParams
A focused JavaScript lesson about URL & URLSearchParams, with examples, common mistakes, self-checks and practical browser context.
Open lessonFormData
A focused JavaScript lesson about FormData, with examples, common mistakes, self-checks and practical browser context.
Open lessonBlob & File
A focused JavaScript lesson about Blob & File, with examples, common mistakes, self-checks and practical browser context.
Open lessonRequest, Response & Headers
A focused JavaScript lesson about Request, Response & Headers, with examples, common mistakes, self-checks and practical browser context.
Open lessonTyped Arrays
A focused JavaScript lesson about Typed Arrays, with examples, common mistakes, self-checks and practical browser context.
Open lessonArrayBuffer, DataView & Atomics
A focused JavaScript lesson about ArrayBuffer, DataView & Atomics, with examples, common mistakes, self-checks and practical browser context.
Open lessonRegular Expressions
Search and validate text without turning patterns into noise.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you write a small RegExp and also explain why a simpler string method may be better?
RegExp
A focused JavaScript lesson about RegExp, with examples, common mistakes, self-checks and practical browser context.
Open lessonRegExp Flags
A focused JavaScript lesson about RegExp Flags, with examples, common mistakes, self-checks and practical browser context.
Open lessonClasses & Assertions
A focused JavaScript lesson about Classes & Assertions, with examples, common mistakes, self-checks and practical browser context.
Open lessonGroups & Quantifiers
A focused JavaScript lesson about Groups & Quantifiers, with examples, common mistakes, self-checks and practical browser context.
Open lessonRegExp Methods
A focused JavaScript lesson about RegExp Methods, with examples, common mistakes, self-checks and practical browser context.
Open lessonErrors & Debugging
Find problems quickly and handle failures cleanly.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you reproduce a bug, inspect state, isolate cause and handle the failure path cleanly?
Errors
A focused JavaScript lesson about Errors, with examples, common mistakes, self-checks and practical browser context.
Open lessontry, catch & throw
A focused JavaScript lesson about try, catch & throw, with examples, common mistakes, self-checks and practical browser context.
Open lessonError Objects
A focused JavaScript lesson about Error Objects, with examples, common mistakes, self-checks and practical browser context.
Open lessonCustom Errors
A focused JavaScript lesson about Custom Errors, with examples, common mistakes, self-checks and practical browser context.
Open lessonConsole Debugging
A focused JavaScript lesson about Console Debugging, with examples, common mistakes, self-checks and practical browser context.
Open lessonBreakpoints & debugger
A focused JavaScript lesson about Breakpoints & debugger, with examples, common mistakes, self-checks and practical browser context.
Open lessonAsync Debugging
A focused JavaScript lesson about Async Debugging, with examples, common mistakes, self-checks and practical browser context.
Open lessonDOM & HTML Interaction
Connect JavaScript to real HTML documents.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you update the DOM safely with textContent, templates and replaceChildren before reaching for innerHTML?
The DOM
A focused JavaScript lesson about The DOM, with examples, common mistakes, self-checks and practical browser context.
Open lessonSelecting Elements
A focused JavaScript lesson about Selecting Elements, with examples, common mistakes, self-checks and practical browser context.
Open lessonChanging Content
A focused JavaScript lesson about Changing Content, with examples, common mistakes, self-checks and practical browser context.
Open lessonAttributes & Properties
A focused JavaScript lesson about Attributes & Properties, with examples, common mistakes, self-checks and practical browser context.
Open lessonclassList & Styles
A focused JavaScript lesson about classList & Styles, with examples, common mistakes, self-checks and practical browser context.
Open lessonCreate & Remove Elements
A focused JavaScript lesson about Create & Remove Elements, with examples, common mistakes, self-checks and practical browser context.
Open lessonDOM Navigation
A focused JavaScript lesson about DOM Navigation, with examples, common mistakes, self-checks and practical browser context.
Open lessondataset & Templates
A focused JavaScript lesson about dataset & Templates, with examples, common mistakes, self-checks and practical browser context.
Open lessonEvents & Forms
React to users without breaking the interface.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you make interaction work with keyboard, focus, validation messages and clear submit states?
Events
A focused JavaScript lesson about Events, with examples, common mistakes, self-checks and practical browser context.
Open lessonEvent Listeners
A focused JavaScript lesson about Event Listeners, with examples, common mistakes, self-checks and practical browser context.
Open lessonEvent Object
A focused JavaScript lesson about Event Object, with examples, common mistakes, self-checks and practical browser context.
Open lessonBubbling & Capturing
A focused JavaScript lesson about Bubbling & Capturing, with examples, common mistakes, self-checks and practical browser context.
Open lessonEvent Delegation
A focused JavaScript lesson about Event Delegation, with examples, common mistakes, self-checks and practical browser context.
Open lessonMouse & Keyboard Events
A focused JavaScript lesson about Mouse & Keyboard Events, with examples, common mistakes, self-checks and practical browser context.
Open lessonForms
A focused JavaScript lesson about Forms, with examples, common mistakes, self-checks and practical browser context.
Open lessonForm Validation
A focused JavaScript lesson about Form Validation, with examples, common mistakes, self-checks and practical browser context.
Open lessonAsync JavaScript
Load data, wait for work and keep interfaces responsive.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you explain loading, success, error, cancellation and the event loop in one async workflow?
Async Introduction
A focused JavaScript lesson about Async Introduction, with examples, common mistakes, self-checks and practical browser context.
Open lessonEvent Loop
A focused JavaScript lesson about Event Loop, with examples, common mistakes, self-checks and practical browser context.
Open lessonTimers
A focused JavaScript lesson about Timers, with examples, common mistakes, self-checks and practical browser context.
Open lessonPromises
A focused JavaScript lesson about Promises, with examples, common mistakes, self-checks and practical browser context.
Open lessonPromise Composition
A focused JavaScript lesson about Promise Composition, with examples, common mistakes, self-checks and practical browser context.
Open lessonasync & await
A focused JavaScript lesson about async & await, with examples, common mistakes, self-checks and practical browser context.
Open lessonFetch
A focused JavaScript lesson about Fetch, with examples, common mistakes, self-checks and practical browser context.
Open lessonAbortController & Streams
A focused JavaScript lesson about AbortController & Streams, with examples, common mistakes, self-checks and practical browser context.
Open lessonModules & Code Organization
Split JavaScript into files that can grow.
This chapter is now a complete lesson group with explanations, runnable examples, why-it-matters sections, practical exercises and production-focused self-checks.
Chapter checkpoint
Can you split code into files with exports, imports and a structure another developer can search?
JavaScript Modules
A focused JavaScript lesson about JavaScript Modules, with examples, common mistakes, self-checks and practical browser context.
Open lessonExport & Import
A focused JavaScript lesson about Export & Import, with examples, common mistakes, self-checks and practical browser context.
Open lessonDefault & Namespace Imports
A focused JavaScript lesson about Default & Namespace Imports, with examples, common mistakes, self-checks and practical browser context.
Open lessonDynamic Import
A focused JavaScript lesson about Dynamic Import, with examples, common mistakes, self-checks and practical browser context.
Open lessonimport.meta
A focused JavaScript lesson about import.meta, with examples, common mistakes, self-checks and practical browser context.
Open lessonFile Structure & npm
A focused JavaScript lesson about File Structure & npm, with examples, common mistakes, self-checks and practical browser context.
Open lessonBrowser APIs & BOM
Use the browser as a real application platform.
This chapter covers the browser environment around JavaScript: storage, location, workers, observers and offline-capable APIs.
Chapter checkpoint
Can you use browser APIs with permission, privacy, fallback and unsupported-browser states in mind?
Window
A focused JavaScript lesson about Window, with examples, common mistakes, self-checks and practical browser context.
Open lessonScreen, Location & History
A focused JavaScript lesson about Screen, Location & History, with examples, common mistakes, self-checks and practical browser context.
Open lessonNavigator
A focused JavaScript lesson about Navigator, with examples, common mistakes, self-checks and practical browser context.
Open lessonlocalStorage & sessionStorage
A focused JavaScript lesson about localStorage & sessionStorage, with examples, common mistakes, self-checks and practical browser context.
Open lessonCookies
A focused JavaScript lesson about Cookies, with examples, common mistakes, self-checks and practical browser context.
Open lessonClipboard API
A focused JavaScript lesson about Clipboard API, with examples, common mistakes, self-checks and practical browser context.
Open lessonGeolocation & Notifications
A focused JavaScript lesson about Geolocation & Notifications, with examples, common mistakes, self-checks and practical browser context.
Open lessonIntersection & Resize Observer
A focused JavaScript lesson about Intersection & Resize Observer, with examples, common mistakes, self-checks and practical browser context.
Open lessonWorkers, IndexedDB & Cache API
A focused JavaScript lesson about Workers, IndexedDB & Cache API, with examples, common mistakes, self-checks and practical browser context.
Open lessonWeb Components & Accessibility
Build components that remain usable.
This chapter connects reusable browser components with semantic HTML, focus management, keyboard support and ARIA feedback.
Chapter checkpoint
Can you build a reusable component without hiding meaning, focus or keyboard behavior?
Custom Elements
A focused JavaScript lesson about Custom Elements, with examples, common mistakes, self-checks and practical browser context.
Open lessonShadow DOM
A focused JavaScript lesson about Shadow DOM, with examples, common mistakes, self-checks and practical browser context.
Open lessonSlots
A focused JavaScript lesson about Slots, with examples, common mistakes, self-checks and practical browser context.
Open lessonWeb Components Lifecycle
A focused JavaScript lesson about Web Components Lifecycle, with examples, common mistakes, self-checks and practical browser context.
Open lessonProgressive Enhancement
A focused JavaScript lesson about Progressive Enhancement, with examples, common mistakes, self-checks and practical browser context.
Open lessonFocus & Keyboard Navigation
A focused JavaScript lesson about Focus & Keyboard Navigation, with examples, common mistakes, self-checks and practical browser context.
Open lessonARIA Live & Modals
A focused JavaScript lesson about ARIA Live & Modals, with examples, common mistakes, self-checks and practical browser context.
Open lessonAdvanced JavaScript
Learn the deep language features professionals meet in real code.
This chapter covers deeper language mechanics such as iterators, generators, proxies, weak references and resource cleanup.
Chapter checkpoint
Can you recognize advanced features and also decide when not to use them?
Iterators
A focused JavaScript lesson about Iterators, with examples, common mistakes, self-checks and practical browser context.
Open lessonGenerators
A focused JavaScript lesson about Generators, with examples, common mistakes, self-checks and practical browser context.
Open lessonAsync Iterators
A focused JavaScript lesson about Async Iterators, with examples, common mistakes, self-checks and practical browser context.
Open lessonProxy & Reflect
A focused JavaScript lesson about Proxy & Reflect, with examples, common mistakes, self-checks and practical browser context.
Open lessonMeta Programming
A focused JavaScript lesson about Meta Programming, with examples, common mistakes, self-checks and practical browser context.
Open lessonMemory Management
A focused JavaScript lesson about Memory Management, with examples, common mistakes, self-checks and practical browser context.
Open lessonWeakRef & FinalizationRegistry
A focused JavaScript lesson about WeakRef & FinalizationRegistry, with examples, common mistakes, self-checks and practical browser context.
Open lessonResource Management
A focused JavaScript lesson about Resource Management, with examples, common mistakes, self-checks and practical browser context.
Open lessonGraphics, Media & UI
Use JavaScript for richer visual interfaces.
This chapter turns JavaScript into visual interface work with canvas, animation, drag and drop and data-driven visuals.
Chapter checkpoint
Can you add motion or visual UI while respecting reduced motion, input method and accessibility?
Canvas with JavaScript
A focused JavaScript lesson about Canvas with JavaScript, with examples, common mistakes, self-checks and practical browser context.
Open lessonWeb Animations API
A focused JavaScript lesson about Web Animations API, with examples, common mistakes, self-checks and practical browser context.
Open lessonDOM Animations
A focused JavaScript lesson about DOM Animations, with examples, common mistakes, self-checks and practical browser context.
Open lessonDrag & Drop
A focused JavaScript lesson about Drag & Drop, with examples, common mistakes, self-checks and practical browser context.
Open lessonCharts & Data Visuals
A focused JavaScript lesson about Charts & Data Visuals, with examples, common mistakes, self-checks and practical browser context.
Open lessonSecurity & Performance
Ship JavaScript that is safer and faster.
This chapter turns JavaScript into production code by covering safe DOM updates, CORS, CSP, throttling, memory and performance.
Chapter checkpoint
Can you trace untrusted input to output and measure performance before guessing?
XSS
A focused JavaScript lesson about XSS, with examples, common mistakes, self-checks and practical browser context.
Open lessonSafe DOM Updates
A focused JavaScript lesson about Safe DOM Updates, with examples, common mistakes, self-checks and practical browser context.
Open lessoneval Risks
A focused JavaScript lesson about eval Risks, with examples, common mistakes, self-checks and practical browser context.
Open lessonCORS
A focused JavaScript lesson about CORS, with examples, common mistakes, self-checks and practical browser context.
Open lessonContent Security Policy
A focused JavaScript lesson about Content Security Policy, with examples, common mistakes, self-checks and practical browser context.
Open lessonDebounce & Throttle
A focused JavaScript lesson about Debounce & Throttle, with examples, common mistakes, self-checks and practical browser context.
Open lessonPerformance API
A focused JavaScript lesson about Performance API, with examples, common mistakes, self-checks and practical browser context.
Open lessonMemory Leaks & Layout Thrashing
A focused JavaScript lesson about Memory Leaks & Layout Thrashing, with examples, common mistakes, self-checks and practical browser context.
Open lessonTesting, Tooling & Production
Move from snippets to maintainable production work.
This chapter moves JavaScript from snippets to reliable work with tests, linting, bundlers and production checks.
Chapter checkpoint
Can you describe the release path from linting to tests, build output and final checklist?
Testing JavaScript
A focused JavaScript lesson about Testing JavaScript, with examples, common mistakes, self-checks and practical browser context.
Open lessonUnit Tests
A focused JavaScript lesson about Unit Tests, with examples, common mistakes, self-checks and practical browser context.
Open lessonDOM Tests
A focused JavaScript lesson about DOM Tests, with examples, common mistakes, self-checks and practical browser context.
Open lessonEnd-to-end Tests
A focused JavaScript lesson about End-to-end Tests, with examples, common mistakes, self-checks and practical browser context.
Open lessonLinting & Formatting
A focused JavaScript lesson about Linting & Formatting, with examples, common mistakes, self-checks and practical browser context.
Open lessonBundlers & Vite
A focused JavaScript lesson about Bundlers & Vite, with examples, common mistakes, self-checks and practical browser context.
Open lessonJavaScript Production Checklist
A focused JavaScript lesson about JavaScript Production Checklist, with examples, common mistakes, self-checks and practical browser context.
Open lessonProjects & Practice
Turn the course into real browser projects.
This chapter turns the course into small browser projects that combine state, events, forms, APIs and rendering.
Chapter checkpoint
Can you define done with accessibility, error states, keyboard flow, responsiveness and production notes?
Counter Project
A focused JavaScript lesson about Counter Project, with examples, common mistakes, self-checks and practical browser context.
Open lessonEvent Listener Project
A focused JavaScript lesson about Event Listener Project, with examples, common mistakes, self-checks and practical browser context.
Open lessonTo-do List Project
A focused JavaScript lesson about To-do List Project, with examples, common mistakes, self-checks and practical browser context.
Open lessonModal Project
A focused JavaScript lesson about Modal Project, with examples, common mistakes, self-checks and practical browser context.
Open lessonForm Validation Project
A focused JavaScript lesson about Form Validation Project, with examples, common mistakes, self-checks and practical browser context.
Open lessonAPI Fetch Project
A focused JavaScript lesson about API Fetch Project, with examples, common mistakes, self-checks and practical browser context.
Open lessonMini Dashboard Project
A focused JavaScript lesson about Mini Dashboard Project, with examples, common mistakes, self-checks and practical browser context.
Open lesson