This is a glossary of terms used in the lessons. Whenever you see a symbol next to a word or phrase in a lesson, you can click on it to see its definition.

Accessibility

Accessibility refers to the design of products, devices, services, or environments for people with disabilities. In web development, it means creating websites that can be used by everyone, including people with visual, auditory, motor, or cognitive disabilities.

Anchor Element

The anchor element is an HTML element represented by the <a> tag. It is used to create hyperlinks that connect one web page to another or to other resources such as images, videos, or documents. The anchor element typically includes the href attribute, which specifies the URL of the page or resource being linked to.

Assistive Technology

Assistive technology refers to devices or software that help people with disabilities use computers and access the web. Examples include screen readers, magnifiers, and alternative input devices.

Attribute

An attribute provides additional information about an HTML element. It is included in the start tag. For example, in <a href="https://example.com">, The href="https://example.com" attribute specifies the URL the link points to.

CSS

Cascading Style Sheets - code that controls how web pages look and feel.

Debugging

Debugging is the process of identifying and fixing errors or bugs in your code. It involves using tools and techniques to inspect your code, understand its behavior, and correct any issues that arise.

Element

An element is a part of the HTML document defined by a start tag, content, and an end tag. For example, <h1>Hello</h1> is an element that represents a heading with the text "Hello".

GIF

GIF (Graphics Interchange Format) is an image format that supports both static and animated images. It uses lossless compression but is limited to 256 colours, making it suitable for simple graphics and animations.

HTML

HyperText Markup Language - the basic code used to build web pages. Hypertext means the text can contain links to other texts, and Markup refers to the way tags are used to define elements within the page.

HTML Entity

An HTML entity is a special code that represents a character that cannot be easily typed or that has a special meaning in HTML. For example, & is an HTML entity that represents the ampersand (&) character, and © represents the copyright symbol (©).

Hyperlink

A hyperlink is a link from one web page to another, typically using the <a> element in HTML.

Image

An image is a visual representation, such as a photo or graphic, that can be displayed on a web page. In HTML, images are added using the <img> element.

Image Format

An image format is a file format for storing digital images. Common image formats include JPEG, PNG, GIF, SVG, and WebP. Each format has its own advantages and disadvantages, such as compression, transparency, and scalability.

JavaScript

A programming language that adds interactive features to websites.

JPEG

JPEG (Joint Photographic Experts Group) is a commonly used image format that uses lossy compression to reduce file size while maintaining acceptable image quality.

Landmark Element

A landmark element is an HTML element that defines a region of a web page, such as a header, main content area, or footer. These elements help users navigate the page, especially those using assistive technologies.

List

A list is an HTML element that groups related items together. There are different types of lists, including ordered lists (<ol>), unordered lists (<ul>), and description lists (<dl>).

Lossless Compression

Lossless compression is a method of reducing file size without losing any data or quality. PNG is an example of a format that uses lossless compression.

Lossy Compression

Lossy compression is a method of reducing file size by permanently removing some data, which may result in a loss of quality. JPEG is an example of a format that uses lossy compression.

Metadata

Metadata is data that provides information about other data. In the context of images, metadata can include details such as the date the photo was taken, camera settings, and location information.

Pixel

A pixel is the smallest unit of a digital image or display. Pixels are the tiny dots that make up the images on screens, and each pixel can display a specific colour.

Pixelation

Pixelation occurs when an image is displayed at a size larger than its resolution, causing individual pixels to become visible and the image to appear blocky or blurry.

PNG

PNG (Portable Network Graphics) is an image format that uses lossless compression, which means it retains all image data and quality. PNG supports transparency and is often used for graphics with sharp edges, such as logos and icons.

Resolution

Resolution refers to the amount of detail an image holds. Higher resolution means more image detail, which is important for printing and high-quality displays, but also results in larger file sizes.

SVG

SVG (Scalable Vector Graphics) is an image format that uses vector graphics, which means it is made up of paths defined by mathematical equations. SVG images can be scaled to any size without losing quality, making them ideal for logos and icons.

Table

In HTML, a table is used to organise data into rows and columns. Tables are defined using the <table> element, with rows defined by <tr> and cells defined by <td> or <th> for header cells.

Tag

In HTML, a tag is a keyword enclosed in angle brackets that defines an element on the page. For example, <h1> is a tag that defines a top-level heading.

WebP

WebP is an image format developed by Google that provides both lossy and lossless compression. It is designed to create smaller file sizes while maintaining high quality, making it ideal for web use.