0 of 54 lessons done

+ 1 advanced lessons in S2 Pro

Chapter 1 of 10

JavaScript basics

Variables, types, equality, strings, loops, functions, arrays and objects.

9 lessons · 0 done

Variables: let and constlet, const and why not var
Data typesPrimitives, objects and typeof
Equality and truthiness=== vs ==, falsy values, ?? and ||
Strings and template literalsBackticks, interpolation and string methods
Conditions and loopsif, for, for...of, while, continue
FunctionsDeclarations, defaults and arrows
ArraysAdd, transform and filter items
ObjectsProperties, references and keys
Chapter review: JavaScript basicsHarder questions on types, coercion, scope and functions

Chapter 2 of 10

Modern JavaScript

Destructuring, spread, modules, array methods and optional chaining.

6 lessons · 0 done

DestructuringUnpack arrays and objects into names
Spread and restThree dots, two jobs
Array methods in practicefind, some, every and reduce
Modulesexport and import
Optional chaining and ??Read deep values safely
Chapter review: modern JavaScriptHarder questions on destructuring, spread, modules and array methods

Chapter 3 of 10

Async JavaScript

The event loop, promises, async/await and fetch.

5 lessons · 0 done

The event loopWhy setTimeout(…, 0) runs last
Promisesthen, catch and Promise.all
async and awaitPromises that read like normal code
fetch and JSONCall an API from JavaScript
Chapter review: async JavaScriptHarder questions on ordering, errors and timing

Chapter 4 of 10

The browser and the DOM

Select elements, handle events and update the page.

5 lessons · 0 done

Selecting elementsquerySelector and querySelectorAll
EventsReact to clicks and submits
Updating the pagetextContent, classList and new elements
Web storageRemember data in the browser
Chapter review: the browser and the DOMHarder questions on selecting, events and storage

Chapter 5 of 10

Advanced JavaScript

Closures, prototypes, this, generators and performance.

5 lessons · 0 done

ClosuresFunctions that remember
this, call and bindWho is the function being called on?
Classes and prototypesclass syntax over the prototype chain
Iterators and generatorsProduce values one at a time
Chapter review: advanced JavaScriptHarder questions on closures, this, prototypes and generators

Chapter 6 of 10

TypeScript

Add types to JavaScript: annotations, interfaces, unions, generics and the built-in utility types.

9 lessons · 0 done

Types and inferenceAnnotate values and let TypeScript infer the rest
Typing functionsParameter types, return types, optional and default parameters
Object types and interfacesDescribe the shape of an object
Unions and narrowingValues that can be one of several types
Arrays and tuplesLists of one type, and fixed-length lists of mixed types
GenericsWrite one function that works for many types
Utility typesPartial, Pick, Omit, Record and Readonly
Classes and access modifierspublic, private and readonly on class members
Chapter review: TypeScriptHarder questions on inference, unions, generics and keyof

Chapter 7 of 10

JavaScript, in depth

Proxy/Reflect, Symbols, custom errors, property descriptors and WeakMap -- past the basics.

6 lessons · 0 done

Custom errorsExtending Error for errors your code can distinguish and handle
Getters, setters and property descriptorsComputed properties, and controlling exactly how a property behaves
SymbolsGuaranteed-unique values, mainly used as non-colliding object keys
Proxy and ReflectIntercept fundamental operations on an object -- get, set, has, and more
WeakMap and WeakSetCollections that don't prevent their keys from being garbage collected
Checkpoint: JavaScript, in depthRe-test the whole unit

Chapter 8 of 10

Testing & tooling

Vitest, npm/package.json, and reading a stack trace -- the tools around the language itself.

4 lessons · 0 done

Testing with Vitestdescribe, it, expect -- and mocking a dependency
npm and package.jsonDependencies, scripts, and semantic versioning
DebuggingReading a stack trace, and console methods beyond log
Checkpoint: Testing & toolingRe-test the whole unit

Chapter 9 of 10

Node.js & practical JavaScript

Running JS outside the browser: the Node runtime, files, paths, CLI arguments and environment variables.

5 lessons · 0 done

The Node.js runtimeJavaScript outside the browser: modules, globals, and the event loop without a DOM
Reading and writing filesThe fs module: synchronous, callback, and promise-based APIs
Working with pathsThe path module: joining, parsing, and cross-platform file paths
CLI arguments and environment variablesprocess.argv and process.env: how a script reads its own invocation
Checkpoint: Node.js & practical JavaScriptRe-test the whole unit

Chapter 10 of 10S2 Pro

Final exam

Harder problems combining ideas across the whole course: ~30 minutes, mostly real code to write.

1 lessons · 0 done

JavaScript final examS2 ProThe final exam: ~30 minutes, covering the whole course

0 of 54 lessons done

+ 1 advanced lessons in S2 Pro

Chapter 1 of 10

JavaScript basics

Variables, types, equality, strings, loops, functions, arrays and objects.

9 lessons · 0 done

Variables: let and constlet, const and why not var
Data typesPrimitives, objects and typeof
Equality and truthiness=== vs ==, falsy values, ?? and ||
Strings and template literalsBackticks, interpolation and string methods
Conditions and loopsif, for, for...of, while, continue
FunctionsDeclarations, defaults and arrows
ArraysAdd, transform and filter items
ObjectsProperties, references and keys
Chapter review: JavaScript basicsHarder questions on types, coercion, scope and functions

Chapter 2 of 10

Modern JavaScript

Destructuring, spread, modules, array methods and optional chaining.

6 lessons · 0 done

DestructuringUnpack arrays and objects into names
Spread and restThree dots, two jobs
Array methods in practicefind, some, every and reduce
Modulesexport and import
Optional chaining and ??Read deep values safely
Chapter review: modern JavaScriptHarder questions on destructuring, spread, modules and array methods

Chapter 3 of 10

Async JavaScript

The event loop, promises, async/await and fetch.

5 lessons · 0 done

The event loopWhy setTimeout(…, 0) runs last
Promisesthen, catch and Promise.all
async and awaitPromises that read like normal code
fetch and JSONCall an API from JavaScript
Chapter review: async JavaScriptHarder questions on ordering, errors and timing

Chapter 4 of 10

The browser and the DOM

Select elements, handle events and update the page.

5 lessons · 0 done

Selecting elementsquerySelector and querySelectorAll
EventsReact to clicks and submits
Updating the pagetextContent, classList and new elements
Web storageRemember data in the browser
Chapter review: the browser and the DOMHarder questions on selecting, events and storage

Chapter 5 of 10

Advanced JavaScript

Closures, prototypes, this, generators and performance.

5 lessons · 0 done

ClosuresFunctions that remember
this, call and bindWho is the function being called on?
Classes and prototypesclass syntax over the prototype chain
Iterators and generatorsProduce values one at a time
Chapter review: advanced JavaScriptHarder questions on closures, this, prototypes and generators

Chapter 6 of 10

TypeScript

Add types to JavaScript: annotations, interfaces, unions, generics and the built-in utility types.

9 lessons · 0 done

Types and inferenceAnnotate values and let TypeScript infer the rest
Typing functionsParameter types, return types, optional and default parameters
Object types and interfacesDescribe the shape of an object
Unions and narrowingValues that can be one of several types
Arrays and tuplesLists of one type, and fixed-length lists of mixed types
GenericsWrite one function that works for many types
Utility typesPartial, Pick, Omit, Record and Readonly
Classes and access modifierspublic, private and readonly on class members
Chapter review: TypeScriptHarder questions on inference, unions, generics and keyof

Chapter 7 of 10

JavaScript, in depth

Proxy/Reflect, Symbols, custom errors, property descriptors and WeakMap -- past the basics.

6 lessons · 0 done

Custom errorsExtending Error for errors your code can distinguish and handle
Getters, setters and property descriptorsComputed properties, and controlling exactly how a property behaves
SymbolsGuaranteed-unique values, mainly used as non-colliding object keys
Proxy and ReflectIntercept fundamental operations on an object -- get, set, has, and more
WeakMap and WeakSetCollections that don't prevent their keys from being garbage collected
Checkpoint: JavaScript, in depthRe-test the whole unit

Chapter 8 of 10

Testing & tooling

Vitest, npm/package.json, and reading a stack trace -- the tools around the language itself.

4 lessons · 0 done

Testing with Vitestdescribe, it, expect -- and mocking a dependency
npm and package.jsonDependencies, scripts, and semantic versioning
DebuggingReading a stack trace, and console methods beyond log
Checkpoint: Testing & toolingRe-test the whole unit

Chapter 9 of 10

Node.js & practical JavaScript

Running JS outside the browser: the Node runtime, files, paths, CLI arguments and environment variables.

5 lessons · 0 done

The Node.js runtimeJavaScript outside the browser: modules, globals, and the event loop without a DOM
Reading and writing filesThe fs module: synchronous, callback, and promise-based APIs
Working with pathsThe path module: joining, parsing, and cross-platform file paths
CLI arguments and environment variablesprocess.argv and process.env: how a script reads its own invocation
Checkpoint: Node.js & practical JavaScriptRe-test the whole unit

Chapter 10 of 10S2 Pro

Final exam

Harder problems combining ideas across the whole course: ~30 minutes, mostly real code to write.

1 lessons · 0 done

JavaScript final examS2 ProThe final exam: ~30 minutes, covering the whole course

JavaScript course

JavaScript course