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HTML, CSS & JavaScript: a beginner's course

Published 5 min read

HTML, CSS & JavaScript is a short, interactive HTML, CSS and JavaScript course for complete beginners. In 15 sections it shows what each language does: HTML builds the content of a page, CSS styles and lays it out, and JavaScript makes it respond. You write a tag, nest elements, adjust the box model, arrange a layout with flexbox and complete a JavaScript function, with a practice task every few sections.

It is a first step, not a full web development bootcamp. It gives you the core ideas and vocabulary so that longer tutorials, and the Code Editor, make sense.

What the course covers

SectionsTopicWhat you do
1 to 3HTML elements and tags: headings, paragraphs and linksWrite an h2 tag into a ready-made page
4 to 5Nesting elementsDrag elements into the right nested order to build a navigation bar
6 to 8CSS rules and the box modelAdjust padding, border and margin, with the right CSS units, to match a target
9 to 11Layout: flex, block and inlinePick the CSS property that arranges elements as shown
12 to 15JavaScript: what it is for, functions and loopsPut the lines of a function in order so it returns the target text

HTML: the content

An HTML page is built from elements, each wrapped in an opening tag and a closing tag with a slash. <h1> is the biggest heading, <p> is a paragraph and <a> is a link. Elements go inside each other, which is called nesting, and that structure is what CSS and JavaScript work with later.

CSS: the look and the layout

A CSS rule picks elements with a selector and sets properties such as colour. Every element is a box: content, then padding inside the border, then margin outside it. Block elements take the full width, inline ones only the space they need, and flexbox lines children up in a row or column with control over the spacing.

JavaScript: the behaviour

JavaScript changes the page after it loads: updating text, changing styles and responding to clicks. The course introduces two building blocks, the function, a named group of instructions, and the loop, which repeats instructions.

Try a task from the course

An h2 is a second-level heading, used for section titles under the main h1. It needs an opening tag, the text, and a closing tag with a slash:

<h2>My favourite books</h2>

Now add an h2 to a ready-made page, then press Mark to check it in the course.

Practice: create a H2 tag in some pre-made html with a single line text box for the user to code in

Press Mark to have your answer marked in the HTML, CSS & JavaScript course.

Who this course is for

  • Complete beginners who have never written code and want to see what web development involves.
  • Students starting a computing course who need the basics of HTML and CSS.
  • People using AI to build websites who want to understand the code it writes.

What you need to know first

Nothing. You need a browser and the patience to type a few angle brackets carefully. No software has to be installed.

How long it takes

There are 15 short sections. Learners without a plan can open two sections of a course a day, in order, so it takes 8 days that way. A plan removes the daily limit, so you could finish it in one sitting.

Where to go next

Practise in the Code Editor, which has separate HTML, CSS and JavaScript tabs and a live preview. Then the Web Frameworks & Stacks course explains how React, Next.js and Express build on these three languages, and Hosting & Deployment shows how to put a site online.

Interactive calculatorCode EditorWrite HTML, CSS and JavaScript side by side and see the page and console output the moment you run it.

Common questions

Is this HTML, CSS and JavaScript course free?
You can take every section without paying, two sections a day, in order. A plan removes the daily limit and opens any section straight away.
Should I learn HTML, CSS or JavaScript first?
HTML first, because it is the content everything else works on. CSS next, to style and lay it out, then JavaScript to add behaviour. This course follows that order.
What is the difference between HTML, CSS and JavaScript?
HTML describes what is on the page, such as headings, paragraphs and links. CSS describes how it looks and where it sits. JavaScript describes what happens when the user does something.
Is HTML a programming language?
Not in the usual sense. HTML is a markup language: it labels content rather than giving instructions with logic and loops. JavaScript is the programming language of the three.
Can I build a website after this course?
You will be able to make a simple page with headings, text, links, basic styling and a little JavaScript. A full website takes more practice, and the next courses help with that.
Do I need to install anything?
No. The course runs in your browser, and so does the Code Editor for practising.

Revision cards

Say the answer first, then flip the card to check it.

Where to go next

  • Solve it

    Code Editor

    Write and run code right in your browser

    Open the tool
  • Learn it

    HTML, CSS & JavaScript

    Learn how to think like a web developer from the ground up

    Start the course
Read next
Computer Science · Web and APIsOnline code editor for HTML, CSS and JavaScriptWrite HTML, CSS and JavaScript in your browser and see the page and console live, with coding problems that check your answer and a link to share.