JavaScript Advanced
Go beyond the fundamentals: classes & OOP, error handling, Map & Set, regular expressions, the event loop, modules, closures & generators, and professional debugging, testing, and clean-code habits.
Why learn JavaScript Advanced?
JavaScript Fundamentals gets you writing programs that work. This is the course that gets you writing programs a professional would actually approve in a code review: classes that model real entities properly, errors that fail safely instead of crashing silently, and code organized across files the way real projects are structured.
It is 8 modules and 36 lessons: classes and object-oriented programming (with the prototype machinery underneath), error handling, Map, Set, JSON and dates, regular expressions, the event loop and advanced async patterns, ES modules, closures and recursion and generators, and a final module on debugging, testing, and clean-code habits.
It ends with a capstone, Capstone: The Complete Picture, that pulls every module together into one project you build yourself, not just another isolated exercise.
Who this course is for
- Graduates of JavaScript Fundamentals ready for the professional layer
- Self-taught developers whose JavaScript works but whose code style does not
- Anyone about to start React, Node.js, or TypeScript who wants stronger foundations first
- Developers who have never really understood the event loop or closures beyond copy-paste
What you'll build and practice
- Classes with inheritance and private fields, plus an understanding of the prototypes underneath them
- try/catch error handling that recovers instead of crashing, including inside async code
- Map, Set, and JSON-based data handling, plus regex for parsing and validating text
- Code split across ES modules the way real npm projects are structured
- The course capstone: a project that composes classes, async code, and clean-code habits into one program
What you'll learn
JavaScript Advanced is organized into 8 focused modules. By the end you'll be comfortable with:
- Classes & Object-Oriented Programming
- Error Handling
- Collections & Data
- Text Processing & Regular Expressions
- The Event Loop & Advanced Async
- Modules & Code Organization
- Advanced Functions & Iteration
- Professional JavaScript
Course curriculum
36 lessons across 8 modules. Lessons marked Free preview are readable without an account.
Module 1. Classes & Object-Oriented Programming
Bundle data and behaviour together with classes, inheritance, and private fields — and see the prototype machinery underneath
- 8mFrom Functions to ClassesFree preview
Why we bundle data and behaviour together — and how the class keyword turns a blueprint into as many objects as you need.
- 7mMethods, Getters & SettersFree preview
Give your classes behaviour — plus properties that compute themselves and guard their own values.
- 8mInheritance: extends & super
Build specialised classes on top of general ones — without copy-pasting a single method.
- 8mStatic Members & Private Fields
Attach helpers to the class itself with static — and truly lock internal data away with # private fields.
- 8mPrototypes: Under the Hood
Where do methods actually live? Meet the prototype chain — the mechanism behind every class, array method, and string method you've ever used.
- 8mPractice: Object-Oriented Thinking
Put the whole module together — classes, getters, inheritance, statics, and private fields in realistic mini-programs.
Module 2. Error Handling
Read stack traces, recover with try/catch, throw your own errors, and handle failures in async code
- 7mWhen Code Goes Wrong
The three kinds of failure, the anatomy of an error message, and how to read a stack trace like a map back to the bug.
- 7mtry, catch & finally
Stop one bad line from killing your whole program — catch exceptions, recover gracefully, and guarantee cleanup.
- 8mThrowing & Custom Errors
Throw your own exceptions when callers break your rules — and build custom error classes that say exactly what went wrong.
- 8mErrors in Async Code
Rejections, .catch(), try/catch with await — and the famous fetch gotcha that bites every JavaScript developer once.
Module 3. Collections & Data
Map, Set, JSON, localStorage, and dates — the tools for storing, moving, and persisting real data
- 7mMap: Key-Value Pairs Done Right
A purpose-built key-value collection — any key type, a real size, guaranteed order, and no inherited surprises.
- 6mSet: Collections of Unique Values
A collection that physically cannot contain duplicates — plus the one-line array dedupe every developer should know.
- 7mJSON: The Language of Data
How objects become text and text becomes objects — stringify, parse, and the round-trip every API request makes.
- 7mlocalStorage: Data That Survives Refresh
Persist settings, drafts, and progress in the browser — the JSON + localStorage combo behind every 'it remembered me!' moment.
- 8mDates & Times
Create dates, read their parts (mind the zero-indexed months!), measure durations with timestamps, and format for humans and machines.
Module 4. Text Processing & Regular Expressions
Describe text patterns with regex: search, validate, extract, and replace like a professional
- 7mWhat is a Regular Expression?
Describe text patterns instead of exact text — your first regex, the test() method, and the i flag.
- 8mCharacter Classes & Quantifiers
The real regex vocabulary: \d \w \s and [sets] for WHAT to match, + * ? {n} for HOW MANY.
- 8mGroups, match & replace
Go beyond yes/no: extract the matched text with match() and capture groups, find ALL matches with the g flag, and rewrite text with replace.
- 8mPractice: Regex Recipes
Read, predict, and complete real-world patterns — validation, extraction, and cleanup recipes you'll reuse for years.
Module 5. The Event Loop & Advanced Async
How JavaScript really runs your code — plus building promises, running work in parallel, and taming timers
- 9mThe Event Loop
The machinery behind every setTimeout and promise you've ever used — call stack, queues, and the loop that connects them.
- 8mCreating Your Own Promises
Stop only consuming promises — manufacture them: new Promise, resolve/reject, the wait() helper, and promisifying callback APIs.
- 8mPromise Superpowers: all, race & friends
Run promises in parallel instead of one-by-one — Promise.all, allSettled, race, and any, plus the sequential-await trap.
- 8mTimers, Debounce & Throttle
setInterval, cancelling timers — and the two rate-limiting patterns (debounce & throttle) behind every smooth search box.
- 8mPractice: Async Mastery
Event-loop tracing, combinator choices, and a real retry-with-delay helper — the whole module in working code.
Module 6. Modules & Code Organization
Split code across files with import/export, and understand npm, package.json, and real project structure
- 6mWhy Modules Exist
The one-giant-file problem, the global-scope disaster it causes, and the module idea that fixed JavaScript for good.
- 8mimport & export
Named exports, the default export, renaming with as — the sharing syntax you'll write every single day.
- 8mnpm & Real Project Structure
Packages, package.json, node_modules, semver, and the folder layout you'll find in virtually every JavaScript repo on Earth.
Module 7. Advanced Functions & Iteration
Closures for real, recursion, higher-order functions, the iteration protocol, and generators
- 8mClosures for Real
The backpack every function carries — private state without classes, function factories, and the pattern behind debounce.
- 8mRecursion: Functions That Call Themselves
Base case, recursive case, the call stack in action — and the nested-data problems where loops give up and recursion shines.
- 8mHigher-Order Functions
Functions in, functions out — build your own map, write function-makers, and see the pattern that unifies half this course.
- 8mIterators & Iterables
What for...of actually does — the next() contract, why strings/Maps/Sets all 'just work', and making your own objects loopable.
- 8mGenerators: Pausable Functions
function* and yield — functions that pause mid-run and resume on demand, making iterators trivial and infinite sequences possible.
Module 8. Professional JavaScript
Debugging like a pro, writing tests, clean-code habits, and a capstone that ties the whole course together
- 8mDebugging Like a Pro
Beyond console.log: the console's power tools, breakpoints with the debugger keyword, and the hypothesis-driven method professionals actually use.
- 8mTesting Fundamentals
Code that checks your code — test/expect, arrange-act-assert, edge cases, and why pure functions are a tester's best friend.
- 8mClean Code Essentials
Code is read far more than it's written — naming that carries meaning, guard clauses, honest functions, and comments that explain why.
- 12mCapstone: The Complete Picture
One real program — a habit tracker — built from classes, private fields, Map, JSON, localStorage, error handling, async, and closures. Plus your road ahead.
Frequently asked questions
- Do I need JavaScript Fundamentals before starting Advanced?
- Yes, this track assumes everything from Fundamentals: variables, strings, arrays, objects and references, functions, loops, and the async basics like promises and fetch. The first lesson recaps that list explicitly so you can self-check before diving in.
- What does advanced actually mean here, is it just harder syntax?
- No. It is the layer that turns working code into professional code: modeling data with classes instead of loose objects, handling failure on purpose instead of hoping nothing breaks, and organizing a project across files instead of one long script. The syntax is a small part of it.
- Does this course explain how the JavaScript event loop really works?
- Yes, as a dedicated module. You go past the vague idea of asynchronous code into the actual mechanics: the call stack, the task queue, microtasks versus macrotasks, and why promises resolve in the order they do. It is the module most self-taught developers skip and regret skipping.
- Will I actually finish with a project, or is it lessons only?
- There is a real capstone in the final module, Capstone: The Complete Picture, that composes classes, error handling, and the debugging and testing habits from that same module into one program you build yourself.
- Is this course useful if I am heading toward TypeScript next?
- Very. TypeScript Mastery assumes exactly the JavaScript fluency this course builds: classes, closures, async patterns, and module organization. Arriving with shaky fundamentals in any of those makes learning the type system harder than it needs to be.
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