How Code Builds the World
See how the world's most popular programming languages work together like a construction crew to build the apps and websites you use every day.
Like Duolingo, but for How Code Builds the World. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
A short one: 14 levels across 2 sections, about 28 minutes end to end, roughly 6 days at five minutes a day. It moves through The Visible World and The Hidden Engine. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in How Code Builds the World
- HTML tags define the purpose of content
- Headings and paragraphs are structural elements
- HTML does not handle visual styling like colors
- HTML tags like <h1> and <button> create the objects
- CSS properties like color and font-size modify the appearance
- CSS cannot exist without an HTML element to style
- Identifying the role of HTML in defining page content
- Distinguishing between structural and stylistic code
- CSS is stored separately from HTML
- Changing a single CSS file updates the look of the whole site
- HTML content remains untouched during a visual redesign
- Classes act as labels for HTML elements
- Identifying the 'Class' as the link between HTML and CSS
- The structure must exist before styles can be applied to it
- The browser processes HTML and CSS together
- The final 'render' is the result of both languages working at once
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives How Code Builds the World the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
Picture this: you are building a digital house. Which tool do you use to label a block of text as a specific part of the page?
Get it right to open this lesson and 13 more in the app.
Where How Code Builds the World takes you
- 1
The Visible World
- The Skeleton and the Paint
- Making the World Interactive
- 2
The Hidden Engine
- The Digital Filing Cabinet
- The High-Performance Engine
- The Full Digital Handshake
2 sections · 5 units · 14 levels. Built to play, not to enroll.
Tomo is in ChatGPT
Tomo is also a ChatGPT plugin: the same playable courses, built and played inside your chat.
Add Tomo to ChatGPT- What to ask
- “Make me a Tomo course on black holes.” “Turn this chat into a Tomo course.”
- What you get
- Quick questions with instant feedback, hearts and stars, ready to play in about a minute.
- Where it goes
- No sign-up to start. Connect your Tomo account and your streak carries on in the app.
You pick the voice
How Code Builds the World is taught in the Storyteller style: every lesson is a story. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start How Code Builds the World today.
Download Tomo, search How Code Builds the World, and play your first lesson in under a minute.