Start programming for real: variables, strings, decisions, arrays, loops, functions, and objects.
JavaScript is the language that makes the web do things, and this is where you start writing it. The course assumes nothing at all: the first lesson explains what a program even is, your first exercise changes one word inside code that already works, and every idea after that lands in an editor where you type, press Run, and the console answers immediately.
It moves in the smallest steps we could build. Printing, then variables, then numbers, then strings, then decisions, then lists, then loops, then functions, then objects. Every lesson teaches exactly one idea and is followed straight away by a practice, and the goal list shows you precisely what has to be true before you move on. Two of the items are broken on purpose, because reading a bug you did not write is a skill of its own.
You ship four real console programs on the way: a story machine that assembles sentences from data, a scoreboard that crunches a season of numbers, a tip calculator built from small functions, and a quiz engine, which is very close to the kind of program grading you on this platform right now. Finish everything and your certificate is waiting. JavaScript DOM is next, where all of this logic starts moving real pages.
52 Lessons • 56 Practices • 18 Quizzes • 4 Projects · ~11h Total
Not just theory. You finish this course with real work to show.
This is the same in-browser editor every lesson uses. Edit the code, hit Run.
Run code in the browser and see the result immediately. Every lesson works this way.
Stuck? Puff explains the error and nudges you forward, without giving the answer away.
Streaks, diamonds, and certificates. Your progress saves automatically, forever.
Every completed course issues a certificate with a public verification link.
Every certificate has a public verification link employers can check.
One certificate per course. Finish a program and earn its program certificate too.
LinkedIn-ready, with a PDF you can download and attach.
You have never written a line of code. This course is built to be your first one.
Your pages look right and do nothing. This is where behaviour comes from.
You want the fundamentals done properly, not another video you watch at double speed.
JavaScript Basics is free to start, no credit card needed. Some later sections are part of Pro, and finishing every section, including the certificate, needs a Pro plan.
Yes. JavaScript Basics starts by explaining what a program is, and your first exercise changes a single word inside working code. If you can type, you qualify. Every idea is introduced on its own before it is used for anything.
No. Your code runs in the browser on Devpuff: write JavaScript in the editor, press Run, and the console prints the result instantly.
No. This course is pure JavaScript in a console, so it works as a first course. HTML Basics only helps you picture where JavaScript will eventually live.
About eleven hours of hands-on work across nine sections, most items under five minutes. A steady 20 minutes a day finishes it in about six weeks.
Because logic comes first. Variables, loops, and functions are far easier to learn without a page in the way. The very next course, JavaScript DOM, points everything you learn here at real pages.
Yes. Finish every item in JavaScript Basics and Devpuff issues a course certificate with a public link that anyone can verify.
How this course connects to the bigger picture, and what to explore next.
Make pages react: select elements, handle events, read input, and build the page from your data.
Lay out real pages with flexbox, CSS grid, positioning, and responsive design that works on any screen.
Write real web pages by hand: document structure, text, links, lists, images, semantic HTML, and forms.
Free to start, no credit card required. Write real code from the first lesson and keep your progress forever.
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