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Glossary

Plain-language definitions of the terms used across the course, each linked to the lessons where they come up.

Accessibility

The practice of building pages that everyone can use, including people who rely on screen readers, keyboards, or other assistive technology.

Appears in: Anatomy of an HTML document, Semantic structure, Headings as an outline, The document head and SEO basics

aria-label

An attribute that gives an element an accessible name, useful for telling apart two regions of the same type, such as two navigation blocks.

Appears in: Semantic structure, Headings as an outline

Attribute

Extra information added to an element's opening tag, written as a name and value, such as the lang on the html element or the href on a link.

Appears in: Anatomy of an HTML document, Semantic structure, The document head and SEO basics

Body

The part of a document that holds everything a visitor actually sees and interacts with.

Appears in: Anatomy of an HTML document, Semantic structure

Canonical link

A tag that names the one true address for a page, so search engines do not treat several versions of the same URL as separate pages.

Appears in: The document head and SEO basics

Character encoding

The system a browser uses to turn the bytes in a file back into letters and symbols. Setting it to UTF-8 covers nearly every character you are likely to type.

Appears in: Anatomy of an HTML document

div

A generic container with no meaning of its own, used to group elements for styling when no semantic element fits.

Appears in: Semantic structure

Doctype

The line at the very top of an HTML file that tells the browser to use modern standards when rendering the page.

Appears in: Anatomy of an HTML document

Document outline

The nested structure formed by a page's headings, read top to bottom. A clean outline lets people navigate by heading.

Appears in: Headings as an outline

Element

A single building block of a page, written as a tag such as a heading or a paragraph. Most elements have an opening and a closing tag with content in between.

Appears in: Anatomy of an HTML document, Semantic structure

Favicon

The small icon shown in a browser tab and bookmark list, usually linked from the head.

Appears in: The document head and SEO basics

Head

The part of a document that holds information about the page rather than its visible content, such as the title and meta tags. None of it shows in the main window.

Appears in: Anatomy of an HTML document, The document head and SEO basics

Heading

One of the h1 through h6 elements that title a section of content. Together they form the page's outline.

Appears in: Headings as an outline, Semantic structure

HTML

HyperText Markup Language, the set of tags that gives a web page its structure and content. It is the foundation every site is built on.

Appears in: Anatomy of an HTML document

Landmark

A semantic region of a page, such as the header, navigation, main content, or footer, that assistive technology can jump straight to.

Appears in: Semantic structure

lang attribute

An attribute on the html element that names the language of the page, helping screen readers pronounce it correctly and browsers offer to translate it.

Appears in: Anatomy of an HTML document

Meta description

A short sentence in the head that search engines show beneath your title in results. It does not move ranking much, but it earns the click.

Appears in: The document head and SEO basics

Open Graph

A set of meta tags that control how a page looks when its link is shared, including the title, description, and preview image.

Appears in: The document head and SEO basics

Software that reads a page aloud or sends it to a braille display, used by people who are blind or have low vision. It relies on well-structured, semantic HTML.

Appears in: Anatomy of an HTML document, Semantic structure, Headings as an outline

Semantic HTML

Using elements that describe what their content means, such as header, nav, and main, rather than wrapping everything in generic divs. It helps software understand the page.

Appears in: Semantic structure, Headings as an outline

SEO

Search engine optimization, the work of helping search engines understand and surface your pages, much of which comes from clear titles, descriptions, and good structure.

Appears in: The document head and SEO basics

Title

The text in the title element that names the page. It shows in the browser tab, becomes the bookmark name, and is the headline in search results.

Appears in: Anatomy of an HTML document, The document head and SEO basics

Viewport

The visible area of a page on a given screen. A viewport meta tag tells phones to use their real width instead of pretending to be a desktop.

Appears in: Anatomy of an HTML document