The Complete JavaScript Course 2023: From Zero to Expert!

The modern JavaScript course for everyone! Master JavaScript with projects, challenges and theory. Many courses in one!

  • Jonas Schmedtmann
  • 4.73
  • (157885 reviews)
  • 69 hrs
  • 320 lectures
  • Udemy
The Complete JavaScript Course 2023: From Zero to Expert!

What you will learn?

  • Become an advanced, confident, and modern JavaScript developer from scratch
  • Build 6 beautiful real-world projects for your portfolio (not boring toy apps)
  • Become job-ready by understanding how JavaScript really works behind the scenes
  • How to think and work like a developer: problem-solving, researching, workflows
  • JavaScript fundamentals: variables, if/else, operators, boolean logic, functions, arrays, objects, loops, strings, etc.
  • Modern ES6+ from the beginning: arrow functions, destructuring, spread operator, optional chaining (ES2020), etc.
  • Modern OOP: Classes, constructors, prototypal inheritance, encapsulation, etc.
  • Complex concepts like the 'this' keyword, higher-order functions, closures, etc.
  • Asynchronous JavaScript: Event loop, promises, async/await, AJAX calls and APIs
  • How to architect your code using flowcharts and common patterns
  • Modern tools for 2022 and beyond: NPM, Parcel, Babel and ES6 modules
  • Practice your skills with 50+ challenges and assignments (solutions included)
  • Get fast and friendly support in the Q&A area
  • Course pathways: design your unique learning path according to your goals!

Your trainer

Jonas Schmedtmann

Hi, I'm Jonas! I have been identified as one of Udemy's Top Instructors and all my premium courses have recently earned the best-selling status for outstanding performance and student satisfaction.

I'm a full-stack web developer and designer with a passion for building beautiful things from scratch. I've been building websites and apps since 2007 and also have a Master's degree in Engineering.

It was in college where I first discovered my passion for teaching and helping others by sharing all I knew. And that passion brought me to Udemy in 2015, where my students love the fact that I take the time to explain important concepts in a way that everyone can easily understand.

320 lessons

Easy to follow lectures and videos covering subject details.

69 hours

This course includes hours of video material. Watch on-demand, anytime, anywhere.

Certificate of Completion

You will earn a Certificate of Completion at the end of this course.

Course curriculum

Welcome, Welcome, Welcome!22:22

  • Course Structure and Projects05:25
  • Read Before You Start!00:34
  • Watch Before You Start!06:09
  • Migration Guide to v2 + Old Course01:51
  • Setting Up Our Code Editor08:23

  • Section Intro00:53
  • Hello World!05:57
  • A Brief Introduction to JavaScript11:18
  • Linking a JavaScript File15:55
  • Values and Variables16:05
  • Practice Assignments00:23
  • Data Types19:19
  • let, const and var09:58
  • Basic Operators19:31
  • Operator Precedence11:19
  • Coding Challenge #110:28
  • Strings and Template Literals10:57
  • Taking Decisions: if / else Statements12:50
  • Coding Challenge #206:21
  • Type Conversion and Coercion16:40
  • Truthy and Falsy Values10:03
  • Equality Operators: == vs. ===15:41
  • Boolean Logic08:30
  • Logical Operators10:37
  • Coding Challenge #315:07
  • The switch Statement13:10
  • Statements and Expressions06:08
  • The Conditional (Ternary) Operator10:02
  • Coding Challenge #409:11
  • JavaScript Releases: ES5, ES6+ and ESNext14:19

  • Section Intro00:36
  • Activating Strict Mode10:27
  • Functions19:08
  • Function Declarations vs. Expressions10:39
  • Arrow Functions09:52
  • Functions Calling Other Functions10:07
  • Reviewing Functions15:37
  • Coding Challenge #118:12
  • Introduction to Arrays21:34
  • Basic Array Operations (Methods)12:52
  • Coding Challenge #209:36
  • Introduction to Objects06:08
  • Dot vs. Bracket Notation19:21
  • Object Methods23:04
  • Coding Challenge #312:58
  • Iteration: The for Loop11:11
  • Looping Arrays, Breaking and Continuing22:02
  • Looping Backwards and Loops in Loops11:53
  • The while Loop11:52
  • Coding Challenge #415:35

  • Pathways and Section Roadmaps04:08
  • Course Pathways00:07

  • Section Intro00:39
  • Section Roadmap00:22
  • Setting up Prettier and VS Code16:22
  • Installing Node.js and Setting Up a Dev Environment11:32
  • Learning How to Code17:42
  • How to Think Like a Developer: Become a Problem Solver!10:53
  • Using Google, StackOverflow and MDN26:36
  • Debugging (Fixing Errors)05:09
  • Debugging with the Console and Breakpoints19:25
  • Coding Challenge #115:24

  • Section Intro00:40
  • Basic HTML Structure and Elements09:32
  • Attributes, Classes and IDs13:09
  • Basic Styling with CSS12:00
  • Introduction to the CSS Box Model20:57

  • Section Intro00:49
  • Section Roadmap00:29
  • PROJECT #1: Guess My Number!08:47
  • What's the DOM and DOM Manipulation06:48
  • Selecting and Manipulating Elements08:22
  • Handling Click Events12:50
  • Implementing the Game Logic19:33
  • Manipulating CSS Styles08:17
  • Coding Challenge #111:40
  • Implementing Highscores07:47
  • Refactoring Our Code: The DRY Principle15:05
  • PROJECT #2: Modal Window13:21
  • Working With Classes16:55
  • Handling an "Esc" Keypress Event14:11
  • PROJECT #3: Pig Game17:08
  • Rolling the Dice15:58
  • Switching the Active Player15:16
  • Holding Current Score24:55
  • Resetting the Game15:38

  • Section Intro01:31
  • Section Roadmap00:30
  • An High-Level Overview of JavaScript12:11
  • The JavaScript Engine and Runtime13:47
  • Execution Contexts and The Call Stack17:45
  • Scope and The Scope Chain25:37
  • Scoping in Practice21:13
  • Variable Environment: Hoisting and The TDZ11:00
  • Hoisting and TDZ in Practice14:42
  • The this Keyword06:30
  • The this Keyword in Practice13:11
  • Regular Functions vs. Arrow Functions18:04
  • Primitives vs. Objects (Primitive vs. Reference Types)16:06
  • Primitives vs. Objects in Practice14:57

  • Section Intro00:53
  • Section Roadmap00:22
  • Destructuring Arrays19:33
  • Destructuring Objects19:46
  • The Spread Operator (...)21:26
  • Rest Pattern and Parameters19:01
  • Short Circuiting (&& and ||)15:55
  • The Nullish Coalescing Operator (??)03:32
  • Logical Assignment Operators11:39
  • Coding Challenge #114:57
  • Looping Arrays: The for-of Loop07:20
  • Enhanced Object Literals07:02
  • Optional Chaining (?.)16:10
  • Looping Objects: Object Keys, Values, and Entries10:09
  • Coding Challenge #214:30
  • Sets13:18
  • Maps: Fundamentals14:03
  • Maps: Iteration12:41
  • Summary: Which Data Structure to Use?09:40
  • Coding Challenge #309:37
  • Working With Strings - Part 116:53
  • Working With Strings - Part 221:45
  • Working With Strings - Part 321:41
  • Coding Challenge #415:15
  • String Methods Practice16:36

  • Section Intro00:48
  • Section Roadmap00:22
  • Default Parameters09:17
  • How Passing Arguments Works: Value vs. Reference13:36
  • First-Class and Higher-Order Functions05:24
  • Functions Accepting Callback Functions15:20
  • Functions Returning Functions06:36
  • The call and apply Methods16:51
  • The bind Method21:33
  • Coding Challenge #118:47
  • Immediately Invoked Function Expressions (IIFE)07:52
  • Closures19:48
  • More Closure Examples15:30
  • Coding Challenge #205:25

  • Section Intro00:53
  • Section Roadmap00:29
  • Simple Array Methods16:37
  • The new at Method06:04
  • Looping Arrays: forEach13:46
  • forEach With Maps and Sets05:32
  • PROJECT: "Bankist" App09:48
  • Creating DOM Elements18:44
  • Coding Challenge #108:31
  • Data Transformations: map, filter, reduce04:40
  • The map Method15:40
  • Computing Usernames12:14
  • The filter Method06:19
  • The reduce Method20:57
  • Coding Challenge #209:56
  • The Magic of Chaining Methods19:39
  • Coding Challenge #303:57
  • The find Method06:47
  • Implementing Login24:18
  • Implementing Transfers20:54
  • The findIndex Method12:34
  • some and every15:11
  • flat and flatMap09:32
  • Sorting Arrays21:55
  • More Ways of Creating and Filling Arrays20:33
  • Summary: Which Array Method to Use?06:24
  • Array Methods Practice32:21
  • Coding Challenge #423:47

  • Section Intro00:50
  • Section Roadmap00:22
  • Converting and Checking Numbers16:46
  • Math and Rounding18:14
  • The Remainder Operator10:56
  • Numeric Separators06:57
  • Working with BigInt11:18
  • Creating Dates12:55
  • Adding Dates to "Bankist" App22:21
  • Operations With Dates15:27
  • Internationalizing Dates (Intl)17:18
  • Internationalizing Numbers (Intl)19:06
  • Timers: setTimeout and setInterval13:53
  • Implementing a Countdown Timer28:31

  • Section Intro01:04
  • Section Roadmap00:22
  • PROJECT: "Bankist" Website08:49
  • How the DOM Really Works10:36
  • Selecting, Creating, and Deleting Elements20:28
  • Styles, Attributes and Classes21:54
  • Implementing Smooth Scrolling15:56
  • Types of Events and Event Handlers10:33
  • Event Propagation: Bubbling and Capturing05:03
  • Event Propagation in Practice17:46
  • Event Delegation: Implementing Page Navigation18:48
  • DOM Traversing14:35
  • Building a Tabbed Component24:08
  • Passing Arguments to Event Handlers18:43
  • Implementing a Sticky Navigation: The Scroll Event07:55
  • A Better Way: The Intersection Observer API24:00
  • Revealing Elements on Scroll12:39
  • Lazy Loading Images18:30
  • Building a Slider Component: Part 123:16
  • Building a Slider Component: Part 219:35
  • Lifecycle DOM Events09:26
  • Efficient Script Loading: defer and async13:30

  • Section Intro01:07
  • Section Roadmap00:22
  • What is Object-Oriented Programming?20:55
  • OOP in JavaScript10:08
  • Constructor Functions and the new Operator14:19
  • Prototypes14:36
  • Prototypal Inheritance and The Prototype Chain10:58
  • Prototypal Inheritance on Built-In Objects14:46
  • Coding Challenge #107:27
  • ES6 Classes12:57
  • Setters and Getters13:15
  • Static Methods06:24
  • Object.create10:56
  • Coding Challenge #206:00
  • Inheritance Between "Classes": Constructor Functions21:03
  • Coding Challenge #310:37
  • Inheritance Between "Classes": ES6 Classes10:46
  • Inheritance Between "Classes": Object.create08:53
  • Another Class Example10:44
  • Encapsulation: Protected Properties and Methods06:47
  • Encapsulation: Private Class Fields and Methods16:11
  • Chaining Methods04:43
  • ES6 Classes Summary07:11
  • Coding Challenge #408:54

  • Section Intro00:58
  • Section Roadmap00:27
  • Project Overview05:02
  • How to Plan a Web Project17:41
  • Using the Geolocation API08:16
  • Displaying a Map Using Leaflet Library13:48
  • Displaying a Map Marker19:54
  • Rendering Workout Input Form16:42
  • Project Architecture09:28
  • Refactoring for Project Architecture24:05
  • Managing Workout Data: Creating Classes16:18
  • Creating a New Workout34:06
  • Rendering Workouts24:19
  • Move to Marker On Click16:32
  • Working with localStorage25:31
  • Final Considerations05:41

  • Section Intro00:55
  • Section Roadmap00:22
  • Asynchronous JavaScript, AJAX and APIs17:57
  • IMPORTANT: API URL Change00:13
  • Our First AJAX Call: XMLHttpRequest19:10
  • [OPTIONAL] How the Web Works: Requests and Responses13:38
  • Welcome to Callback Hell13:52
  • Promises and the Fetch API09:25
  • Consuming Promises09:24
  • Chaining Promises09:13
  • Handling Rejected Promises16:13
  • Throwing Errors Manually15:24
  • Coding Challenge #116:31
  • Asynchronous Behind the Scenes: The Event Loop17:53
  • The Event Loop in Practice09:15
  • Building a Simple Promise20:17
  • Promisifying the Geolocation API13:26
  • Coding Challenge #215:53
  • Consuming Promises with Async/Await15:06
  • Error Handling With try...catch10:22
  • Returning Values from Async Functions14:39
  • Running Promises in Parallel10:56
  • Other Promise Combinators: race, allSettled and any13:19
  • Coding Challenge #317:30

  • Section Intro00:47
  • Section Roadmap00:22
  • An Overview of Modern JavaScript Development06:38
  • An Overview of Modules in JavaScript15:01
  • Exporting and Importing in ES6 Modules22:38
  • Top-Level await (ES2022)14:44
  • The Module Pattern10:19
  • CommonJS Modules04:24
  • A Brief Introduction to the Command Line12:27
  • Introduction to NPM18:40
  • Bundling With Parcel and NPM Scripts21:39
  • Configuring Babel and Polyfilling18:03
  • Review: Writing Clean and Modern JavaScript10:26
  • Let's Fix Some Bad Code: Part 123:20
  • Declarative and Functional JavaScript Principles12:25
  • Let's Fix Some Bad Code: Part 238:09

  • Section Intro00:56
  • Section Roadmap00:27
  • Project Overview and Planning (I)14:21
  • Latest Code Updates (Parcel v2 and more)00:47
  • Loading a Recipe from API24:11
  • Rendering the Recipe22:23
  • Listening For load and hashchange Events11:02
  • The MVC Architecture16:32
  • Refactoring for MVC38:53
  • Helpers and Configuration Files21:23
  • Event Handlers in MVC: Publisher-Subscriber Pattern15:08
  • Implementing Error and Success Messages11:34
  • Implementing Search Results - Part 125:46
  • Implementing Search Results - Part 228:15
  • Implementing Pagination - Part 112:18
  • Implementing Pagination - Part 237:05
  • Project Planning II03:13
  • Updating Recipe Servings26:40
  • Developing a DOM Updating Algorithm34:22
  • Implementing Bookmarks - Part 125:59
  • Implementing Bookmarks - Part 218:31
  • Storing Bookmarks With localStorage18:22
  • Project Planning III02:08
  • Uploading a New Recipe - Part 117:43
  • Uploading a New Recipe - Part 240:37
  • Uploading a New Recipe - Part 319:58
  • Wrapping Up: Final Considerations14:45

  • Section Intro00:44
  • Section Roadmap00:22
  • Simple Deployment With Netlify11:18
  • Setting Up Git and GitHub07:39
  • Git Fundamentals19:36
  • Pushing to GitHub09:31
  • Setting Up Continuous Integration With Netlify10:06

  • Where to Go from Here03:00
  • My Other Courses + Updates01:03

  • Access the Old Course00:51
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