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A Piccalilli course

Truly understand how JavaScript works

Future-proof your career with this in-depth course from Mat Marquis. You’ll walk away with the confidence that comes with understanding how JavaScript works, to a level that can otherwise take years to unlock.

Take your skillset way beyond syntax expertise

Being a senior level JavaScript developer is not about memorising countless methods and properties, it’s about gaining a fundamental understanding of the way JavaScript “thinks”.

Here’s the rub: there isn’t always time in a project to dig into the how and why — not when there’s work to do and tickets to close. Gaining that understanding through trial and error, copied-and-pasted snippets, or working with frameworks that make tasks quicker and easier by papering over the gritty details can take a person years.

What I’m doing with this course is to teach you how the language works, how it really works, because that knowledge is what sets a truly senior developer apart. After you complete this course, your knowledge of the language will give you unrecognisable levels of confidence and transferable skills that you can apply, regardless of your organisation’s preference in framework.

This course isn’t a catalogue of every method and property JavaScript has to offer; you won’t find any flash cards or vocab quizzes here. We’re going to focus on the syntaxes you’re most likely to encounter in your day-to-day work, the ones that make up more advanced features of the language, and most importantly, the ones that will help you gain a better understanding of JavaScript, the language, as it is played.

My goal isn’t for you to walk away from this course knowing the whole of JavaScript — that’s impossible. My goal is to help you understand JavaScript: why it works the way it does, why sometimes things that feel like they should work don’t, and why things that feel like they shouldn’t work sometimes do. If you should find yourself hitting a wall, don’t stress: I’ll be here to help right alongside your peers in the JavaScript for Everyone Discord community.

— Mat

Take the course for just £249 £189

Let’s take your skillset way beyond syntax expertise

If I wanted to learn something, I’d first check to see if Mat Marquis wrote about it. I know few people as skilled at breaking down complex ideas into human-sized chunks; I know even fewer folks who write with such easy, approachable wit.

I’ve learned so much from Mat over my career, and I’m excited I’ll be learning something new from him real soon. I can’t wait to check out JavaScript for Everyone.

Ethan Marcotte, Designer, writer and creator of responsive web design

I’d read Mat’s writing purely for pleasure. I’ve read a lot of technical writing in my time. It’s a skill to deliver technical correctness with clarity and brevity. Even then, rarely do you end up with anything fun. Mat reads like a grizzled poet, with more curly brackets than em dashes, teaching you just what you need right when you need it. It’s perfect, and you’ll end up wanting more.

Chris Coyier, Co-Founder, CodePen

I have read every single word of this course and let me tell you, it is unbelievable. JavaScript is a complicated language to learn, especially for someone like me, who’s a designer by trade.

Even with that context, I can feel how much better I am at writing JavaScript and how much more confident I am. I’m so thankful to Mat for that, especially.

Andy Bell, Founder, Piccalilli

Why take this course?

Benefits

  • Education from an industry expert

    Your instructor, Mat Marquis has over 20 years in the industry, and an eye-watering depth of experience.

    You may not realize it in the moment, but you’re already familiar with his output — from his pioneering responsive web design work with the Boston Globe, to his time on the jQuery Team, to Chairing The web standards group at the W3C that brought responsive image markup to the web platform.

    Mat is a two-time A Book Apart author, has written multiple courses for Google's web.dev learning platform, and has spoken at conferences like Smashing, Beyond Tellerand, and An Event Apart. In his own words, he “keeps busy.”

  • Skills that will always beat AI reliance

    You might think “it’s ok, I don't need to understand JavaScript too deeply because I can lean on AI” and sure, we understand why people feel like that.

    The problem with AI tools though is they make you a passive developer and when stuff does go wrong — which it always does — by having a deep knowledge of JavaScript from this course, you will be able to tackle those problems head-on and you’ll fully understand what has actually gone wrong, regardless of the framework and tools you use. And beyond that, if you do need or choose to use AI, this depth of knowledge will help you to elevate the output of the tools to match your standards, not the other way around.

  • A long-term guide that you can trust

    The course is designed to be read, lesson-by-lesson, in order, at your own pace, but it’s much more than that.

    You’re going to stumble into issues while you work with JavaScript, so this course, in the long-term, will be a trusted resource you can pick up, again and again to help you out.

    All content updates are free forever as this content evolves to be as useful as possible for everyone.

  • Accessible, highly approachable content

    This course is over 86,000 words. With his highly approachable and digestible writing style and inimitable wit, Mat manages to deliver this depth of content in a way that makes it highly accessible. This is the thing you see, it's all about how you teach.

    Anyone could write a dry, but detailed guide about how JavaScript works, but most people would just gloss over that. Mat gives you the details — oh boy, he does that — but he does so with a rhythm and flow that helps that knowledge to stick. There's no better way to learn than with a smile on your face.

Our end-game is to give you the skills you need for long-term career progression

Let’s get you paid

By learning how and why JavaScript works on a fundamental level, you’ll be in a stronger position to weather the changes our industry is going through.

Our industry is changing, constantly. The AI hype cycle poses an increasing risk to job security, and despite every promise otherwise the output from AI code generators is failing to live up to the hype.

Deep knowledge and skills have never been more important. Understanding JavaScript deeply will mean you’ll be the one that’s called upon to oversee and course correct the AI-generated output. And when the AI bubble does pop, having a deep knowledge of how JavaScript works will put you in a strong position to command more compensation and better terms because you’ll be in the strongest position to fix the mess left behind by AI.

Take the course for just £249 £189

Let’s take your skillset way beyond syntax expertise

Mat’s domain experience, moral compass, and playful rhetoric make him one of my favourite tech writers working today. Whatever he chooses to publish, you can rest assured that reading will broaden your horizons and lighten your spirits.

Mike Pennisi, Worker-owner and engineer at Bocoup

Mat’s writing stands out in an industry that is full of unnecessary over-complication for complication’s sake. He takes technical concepts and breaks them down in a way that is direct, easy to understand, and oftentimes entertaining. JavaScript for Everyone is a gift for anyone looking to improve their understanding of the language that powers the web.

Eric Bailey, Senior Accessibility Designer, GitHub

A lot of folks in tech spend their careers building enormous (and enormously intimidating) walls of complexity. Mat’s made his career out of smashing those walls: breaking ’em down with clarity and concision and making sure everything he puts into the world is inclusive, approachable, and, frankly – fun

Eric Portis, Developer Evangelist, Cloudinary

This course goes deep

Curriculum overview

With over fifty lessons spanning twelve modules, and over 86,000 words, this course will teach you to understand JavaScript deeply. JavaScript is a complicated language to learn, and Mat’s unique, highly approachable writing style brings a rhythm and flow that really helps the knowledge to stick.

See all the modules and lessons

  1. Intro

    1. #1
      Welcome to JavaScript for Everyone
    2. #2
      The Fall and Rise of JavaScript
    3. #3
      Strict Mode is the Greatest

  2. Lexical Grammar

    1. #4
      Intro to Lexical Analysis
    2. #5
      Whitespace and Comments
    3. #6
      Case sensitivity
    4. #7
      Expressions
    5. #8
      Statements

  3. Primitives

    1. #9
      Introduction to Primitives
    2. #10
      Numbers
    3. #11
      Strings
    4. #12
      Booleans
    5. #13
      null and undefined
    6. #14
      BigInt
    7. #15
      Symbol

  4. Variables

    1. #16
      Introduction to Variables
    2. #17
      Identifiers
    3. #18
      Declarations and Variable Scope
    4. #19
      Destructuring Assignment

  5. Indexed Collections

    1. #20
      Introduction to Indexed Collections
    2. #21
      Creating Arrays
    3. #22
      Accessing Array Elements
    4. #23
      Spread Syntax

  6. Keyed Collections

    1. #24
      Intro to Keyed Collections
    2. #25
      Set (and WeakSet)
    3. #26
      Map (and WeakMap)

  7. Objects

    1. #27
      Introduction to Objects
    2. #28
      Creating Properties
    3. #29
      Accessing Properties
    4. #30
      Prototypes and Prototypal Inheritance
    5. #31
      Property Descriptors

  8. Iterables and Iterators

    1. #32
      Introduction to Iterables and Iterators
    2. #33
      Iterables and Iteration
    3. #34
      Iterators
    4. #35
      Iterateds

  9. Functions

    1. #36
      Introduction to Functions
    2. #37
      Defining Functions
    3. #38
      Invoking Functions
    4. #39
      Generator Functions
    5. #40
      Constructor Functions
    6. #41
      this

  10. Classes

    1. #42
      Intro to Classes
    2. #43
      Defining and Invoking Classes
    3. #44
      Class Methods and Properties
    4. #45
      Public Fields
    5. #46
      Private and Static Fields
    6. #47
      Extending Classes

  11. Asynchronous JavaScript

    1. #48
      Introduction to Asynchronous JavaScript
    2. #49
      Creating Promises
    3. #50
      Consuming Promises
    4. #51
      Asynchronous Functions

  12. Wrapping up

    1. #52
      Wrapping Up
    2. #53
      Acknowledgments

Frequently asked questions

Let’s clear up any worries you might have with some quick-fire answers.

  1. What skills do I need to have?

    To get the most from this course, you should have at least fundamental JavaScript skills. You can get those for free in my web.dev Learn JavaScript course. Once you have these basics covered, you’re more than qualified to take the course!

  2. I’m a senior level developer. Is this course worth taking?

    Our job as senior level developers is to maintain an extremely high level of technical knowledge to help our more junior team members, so yes, absolutely.

    It’s also our job to tackle the most difficult of problems in our day-to-day. Having an up to date, deep knowledge of JavaScript is only going to help that.

  3. What other courses/books have you written?

    Mat is the author of JavaScript for Web Designers and Image Performance from A Book Apart. He also wrote the Learn JavaScript and Learn Images courses for Google’s web.dev.

  4. Is there a set timeframe to complete the course?

    The course is in a mixed-media, mostly written format with no timeframe. You can start whenever you like and pick it up when you have time available. There’s no set cohorts or timelines to work to.

  5. How long does the course take?

    Our advice is that the course should take around 15-30 hours to complete. Because this is a written course, and people’s reading speeds are different, your mileage might vary, however.

  6. What’s the refund policy?

    We’re confident that you’re going to get a lot of value from this course, but if you are not happy with your purchase within 14 days, please get in touch and we’ll refund your purchase in full.

  7. The price is in GBP, does that mean it’s UK only?

    Not at all, it’s for everyone, globally. We charge in GBP because we are a UK-based company. Stripe, our payment processor, will charge you in your local currency.

  8. Do you offer Purchasing Power Parity (PPP)?

    If you’re coming in from a supported PPP country, you’ll see a discount code before you check out. If there is a promotion running — for example, a launch discount — we will present the cheapest price for you; either PPP or promotion discount. PPP discounts are applied to the full price of the course.

    If you’re coming in from a country that normally receives a PPP discount but we haven’t provided a discount code, please get in touch and our support team will be more than happy to help you out.

  9. Do you offer bulk discounts for companies?

    We do indeed! Head over to our company licences page to see our available discounts, order your company licence and see options for more complicated billing needs (don't worry, we get it).

About your instructor

A course by Mat Marquis

My name is Mat “Wilto” Marquis, and I build websites. I’m an independent designer, front-end developer, and consultant.

Profile shot of Mat Marquis

I’m also a retired amateur boxer, halfway decent cook, passable carpenter, bumbling antique British motorcycle mechanic, urban beekeeper, and occasional zine editor. I keep busy.

I've been building websites for almost twenty years now, working with clients like Microsoft, ProPublica, Axios, and the Boston Globe. My areas of expertise are accessibility and front-end performance, and my goal is to build a web that can better reach users in any browsing context, regardless of the size of their screen, the speed of their internet connection, the age of their device, or the combination of browsers and assistive technologies they use.

In the past I've been a member of the jQuery Team, an editor of the HTML specification, author of multiple books with A Book Apart, speaker at conferences like An Event Apart and Smashing Conference — I was even in the movie What Comes Next is the Future to discuss my role as Chair of the group responsible for bringing responsive image markup to the web platform. I’ve got an IMDB page for it and everything!

Just—… just ignore the other thing on there.

Long story.

Let’s take your JavaScript skills further than you ever thought possible

Take the course

Take the course for just £249 £189

What you get:

  • Support and community

    Everyone who purchases JavaScript for Everyone gets access to an exclusive Discord community where you can get support from your instructor and your peers.

  • Comprehensive, structured learning

    The course is delivered in an accessible, mixed media format that’s easy to consume and easy to pick up where you left off.

  • Lifetime access

    Pay once and get lifetime access to all the current and future course material.

  • A certificate of completion

    It’s really important for some organisations that you get a certificate of completion. We’ve got your back with that.

  • Customer support

    Our customer support team are ready to help out with queries whenever you have them.

  • Effective use of training budgets

    You’ll learn transferable and high quality, applicable skills, making this a sound investment of your training budget.

Join over 1,800 others, taking our courses to super-charge their career prospects, for just £249 £189

Price excludes sales tax/VAT where applicable. Tax will be calculated at checkout for you.

Enter the email that you want to access your course with and we’ll send you to Stripe to complete your purchase, where you can also apply coupon codes.

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