HTML is the structure, CSS is the paint — and JavaScript is the behaviour: it reacts to clicks, changes the page, and talks to servers. Everything runs live in your browser here (no install), and across this track you'll build one small Notes app — first in plain JavaScript, then React, then a real backend.
A tiny notes list: type a note, it appears; tick it done; delete it. That's it — small on purpose, so you can hold the whole thing in your head while we go from a single JavaScript file → React components → a Node/Express server with a real API. Same app, three layers.
Where JS runs, and your very first line of live code in the browser.
Boxes for values — let, const, strings, numbers, booleans.
Reusable recipes: inputs in, a result out. Arrow functions too.
Lists and labelled records — how we'll model a note and a list of notes.
Reach into the page from JS: find, create and change elements. Render the notes.
React to the user — the "Add note" button that actually adds a note.
Talk to a server: load and save notes over the network (mocked live here).
Assemble it all into a working notes app — in pure JavaScript.
Saved in your browser — close the tab and pick up where you left off.