Web Design Glossary
Plain-English definitions for Bootstrap 5, HTML templates, CSS layout, and front-end development terms.
A
Above the Fold
Above the fold refers to the portion of a web page visible without scrolling. The term originates from newspaper printin…
A/B Testing
A/B testing (also called split testing) is a controlled experiment where two versions of a web page, email, or element (…
Above the Fold in Web Design
Above the Fold in Web Design is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Unders…
B
Bootstrap 5
Bootstrap 5 is a free, open-source CSS and JavaScript framework used to build responsive, mobile-first websites. Release…
Bootstrap Grid
The Bootstrap grid system is a responsive, 12-column layout framework built on CSS flexbox. It uses a series of containe…
Breadcrumbs
Breadcrumbs are a secondary navigation element that shows users their current location within a website's hierarchy — ty…
Bootstrap 5 Navbar Component
The Bootstrap 5 Navbar component is a responsive navigation header built on Flexbox that provides a collapsible, accessi…
Bounce Rate
Bounce rate is the percentage of sessions in which a user lands on a page and exits without triggering any additional re…
Bootstrap 5 Modal Component
The Bootstrap 5 Modal component is a layered dialog overlay system built on top of the HTML `<dialog>`-inspired pattern,…
Bootstrap 5 Sizing Utilities
Bootstrap 5 Sizing Utilities are a set of CSS helper classes that control the width and height of elements using predefi…
Browser Caching
Browser caching is a mechanism by which a web browser stores local copies of static assets — HTML, CSS, JavaScript, imag…
Bootstrap 5 Shadow Utilities
Bootstrap 5 Shadow Utilities is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Unders…
Bootstrap 5 Display Headings
Bootstrap 5 Display Headings are a set of six utility classes (.display-1 through .display-6) that render oversized, vis…
Bootstrap 5 Flexbox Utilities
Bootstrap 5 Flexbox Utilities are a set of CSS utility classes that expose the CSS Flexible Box Layout Module (Flexbox) …
Bootstrap 5 Typography
Bootstrap 5 Typography is the typographic foundation built into Bootstrap 5's CSS framework, providing a default type sc…
Bootstrap 5 Position Utilities
Bootstrap 5 Position Utilities are a set of CSS helper classes that control the CSS `position` property and related offs…
Bootstrap 5 Color Utilities
Bootstrap 5 Color Utilities are a set of CSS utility classes that apply foreground text colors, background colors, and g…
Breadcrumb Navigation
Breadcrumb navigation is a secondary navigation pattern that displays a user's current location within a site's hierarch…
Bootstrap 5 Text Utilities
Bootstrap 5 Text Utilities is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Understa…
Bootstrap 5 Font Weight Utilities
Bootstrap 5 Font Weight Utilities is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. U…
Bootstrap 5 Card Component
Bootstrap 5 Card Component is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Understa…
Bootstrap 5 Font Size Classes
Bootstrap 5 font size utility classes are a set of predefined CSS classes (`fs-1` through `fs-6`) that apply responsive,…
Bootstrap 5 Carousel
The Bootstrap 5 Carousel is a slideshow component built on CSS transitions and the Bootstrap JavaScript plugin system, e…
Bootstrap 5 Table Classes
Bootstrap 5 Table Classes is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Understan…
Bootstrap 5 Spacing Utilities
Bootstrap 5 Spacing Utilities are a set of CSS utility classes that apply margin and padding values to elements using a …
C
CSS Flexbox
CSS Flexbox (Flexible Box Layout) is a CSS layout model that makes it easy to align and distribute space among items in …
CSS Grid
CSS Grid Layout is a two-dimensional layout system that lets you create complex web layouts by defining both rows and co…
Call to Action (CTA)
A call to action (CTA) is a design element — typically a button or link — that prompts users to take a specific, desired…
CSS Framework
A CSS framework is a pre-built library of CSS (and often JavaScript) that provides a foundation for web development — in…
Canvas Template
Canvas Template is a premium Bootstrap 5 HTML template created by SemiColonWeb, available on ThemeForest (Envato Market)…
Canonical URL
A canonical URL is the preferred version of a web page URL that you designate as the 'master' version when multiple URLs…
Core Web Vitals
Core Web Vitals are a set of real-world performance metrics defined by Google that measure the user experience of a web …
Colour Contrast
Colour contrast in web design refers to the difference in luminance between a foreground colour (typically text) and its…
CSS Custom Properties (Variables)
CSS custom properties — commonly called CSS variables — are entities defined by CSS authors that contain specific values…
CDN (Content Delivery Network)
A Content Delivery Network (CDN) is a geographically distributed network of servers that caches and delivers web content…
Conversion Rate
Conversion rate is the percentage of website visitors who complete a desired action — signing up, purchasing, downloadin…
CDN (Content Delivery Network)
A Content Delivery Network (CDN) is a geographically distributed network of proxy servers that cache content closer to e…
CSS Animation
CSS animation is a native browser feature that lets developers create smooth visual transitions and motion effects on HT…
Click-Through Rate (CTR)
Click-through rate (CTR) is the percentage of search impressions that result in a click. CTR = clicks / impressions. A l…
CSS Media Query
A CSS media query is a conditional rule defined in the CSS3 Media Queries specification (W3C) that applies styles only w…
CSS Gradient Background
A CSS gradient background is a programmatically generated image created entirely in CSS using functions like linear-grad…
CSS Position Property
The CSS `position` property controls how an element is placed in the document flow and how it establishes a positioning …
CSS Box Model
The CSS Box Model is the foundational layout algorithm defined in the CSS2 specification (and refined in CSS3) that trea…
CSS text-shadow Property
The CSS `text-shadow` property applies one or more shadow effects to text characters, accepting a comma-separated list o…
CSS Pseudo-Classes
CSS pseudo-classes are keywords added to a selector that specify a special state of the selected element, defined in the…
CSS Transform
CSS Transform is a CSS module that allows elements to be visually repositioned, scaled, rotated, or skewed in 2D or 3D s…
CSS3
CSS3 is the third major iteration of the Cascading Style Sheets specification, introducing modular sub-specifications th…
CSS Position Sticky
CSS Position Sticky is a hybrid positioning model defined in the CSS Positioning Level 3 specification that allows an el…
Conversion Rate Optimisation (CRO)
Conversion Rate Optimisation (CRO) is the systematic process of increasing the percentage of website visitors who comple…
CSS Display Property
The CSS `display` property determines how an element generates a box in the document layout flow, controlling both the e…
CSS border-radius Property
The CSS `border-radius` property rounds the corners of an element's outer border edge by defining the radii of elliptica…
Cumulative Layout Shift (CLS)
Cumulative Layout Shift (CLS) is a Core Web Vital metric developed by Google that quantifies the visual stability of a w…
CSS Overflow Property
The CSS `overflow` property controls how a browser renders content that exceeds the boundaries of its containing block e…
CSS Specificity
CSS Specificity is the algorithm browsers use to determine which CSS rule takes precedence when multiple conflicting dec…
D
Dark Mode
Dark mode is a display setting that uses a dark (typically near-black) background with light-coloured text, replacing th…
Dwell Time
Dwell time is the duration a user spends on a webpage after clicking through from a search engine results page (SERP) be…
Defer vs Async Scripts
The `defer` and `async` attributes on HTML `<script>` tags control how the browser fetches and executes JavaScript relat…
Domain Name
A domain name is a human-readable address (e.g., example.com) that maps to one or more IP addresses through the Domain N…
E
F
Front-End Development
Front-end development is the discipline of building the client-side (user-facing) portion of websites and web applicatio…
Favicon
A favicon (short for 'favourite icon') is the small icon associated with a website, displayed in browser tabs, bookmark …
F-Pattern Layout
The F-Pattern Layout is a web design approach modeled after eye-tracking research showing that users scan web pages in a…
Financial Website Design
Financial Website Design is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Understand…
Favicon Sizes Guide
A favicon sizes guide is a specification framework defining the exact pixel dimensions, file formats, and HTML link decl…
Font-display: swap
Font-display: swap is a CSS @font-face descriptor defined in the CSS Fonts Level 4 specification that instructs the brow…
Flexbox vs CSS Grid
Flexbox (CSS Flexible Box Layout) and CSS Grid are two distinct CSS layout modules that solve different dimensional prob…
G
Google Analytics
Google Analytics (GA) is a free web analytics service provided by Google that tracks and reports website traffic, user b…
Gzip Compression
Gzip is a file compression format that reduces the size of text-based resources (HTML, CSS, JS) sent from your server. E…
Git
Git is a distributed version control system (DVCS) created by Linus Torvalds in 2005 that tracks changes to files over t…
H
HTML Template
An HTML template is a pre-written HTML file (or collection of files) that provides a ready-made structure for a web page…
Hero Section
A hero section is the large, prominent area at the top of a web page — the first thing visitors see when they land on th…
HTTP/2 vs HTTP/3
HTTP/2 and HTTP/3 are modern web protocols that replace HTTP/1.1. HTTP/2 enables multiplexing (multiple requests over on…
Hreflang Tag
Hreflang Tag is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Understanding Hreflang…
HTML Head Elements
HTML head elements are tags placed within the <head> section of an HTML document that provide metadata, resource links, …
How to Add Favicon in HTML
A favicon (short for 'favorites icon') is a small icon — typically 16×16, 32×32, or 48×48 pixels — associated with a web…
HTTP vs HTTPS
HTTP (HyperText Transfer Protocol) and HTTPS (HTTP Secure) are the foundational application-layer protocols governing da…
Healthcare Website Design
Healthcare website design is the specialized practice of building patient-facing and clinical web properties that comply…
HTML5
HTML5 is the fifth and current major version of the HyperText Markup Language, standardized by the W3C and WHATWG, intro…
I
Internal Linking
Internal linking is the practice of hyperlinking from one page of a website to another page on the same domain. Unlike e…
International SEO
International SEO is the practice of optimizing a website so that search engines can correctly identify which countries …
Interaction to Next Paint (INP)
Interaction to Next Paint (INP) is a Core Web Vital metric that measures the latency from a user's input event (click, t…
J
K
L
Landing Page
A landing page is a standalone web page designed with a single, focused objective — to convert visitors into leads, cust…
Lazy Loading
Lazy loading is a performance technique that defers the loading of non-critical resources (typically images and iframes)…
Local SEO
Local SEO optimises a website to appear in local search results when users search for products or services in a specific…
Largest Contentful Paint (LCP)
Largest Contentful Paint (LCP) is a Core Web Vital metric defined by the W3C Largest Contentful Paint specification that…
Law Firm Website Design
Law Firm Website Design is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Understandi…
Landing Page Sections
Landing page sections are discrete, full-width structural blocks within a single-page or campaign-focused HTML document,…
Largest Contentful Paint (LCP)
Largest Contentful Paint (LCP) is a Core Web Vital metric defined by the W3C Largest Contentful Paint specification that…
M
O
Open Graph
Open Graph (OG) is a protocol developed by Facebook that enables web pages to become rich objects in social media. By ad…
Open Graph Checker
Open Graph Checker is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Understanding Op…
OG Image (Open Graph Image)
An OG Image (Open Graph Image) is a specific meta tag defined by the Open Graph Protocol (ogp.me) that designates which …
P
Page Speed
Page speed refers to how quickly a web page loads and becomes usable for visitors. It's measured by multiple metrics — T…
Progressive Web App (PWA)
A Progressive Web App (PWA) is a web application that uses modern browser APIs — primarily Service Workers, the Web App …
Preconnect & DNS Prefetch
Preconnect and DNS Prefetch are HTML resource hint directives that instruct the browser to perform early network setup f…
People Also Ask
People Also Ask is a web development concept relevant to modern HTML, CSS, and JavaScript workflows. Understanding Peopl…
Performance Budget
A performance budget is a set of quantitative limits placed on metrics that affect a website's load time, rendering spee…
R
Responsive Design
Responsive web design (RWD) is an approach to web development where a website's layout and content automatically adapt t…
Robots.txt
Robots.txt is a plain text file placed at the root of a website (e.g. https://example.com/robots.txt) that provides inst…
Render-Blocking Resources
Render-blocking resources are third-party files — primarily CSS stylesheets and synchronous JavaScript — that the browse…
REST API
REST (Representational State Transfer) API is an architectural style for distributed hypermedia systems, defined by Roy …
REST API
REST (Representational State Transfer) API is an architectural style for designing networked applications where clients …
RankBrain
RankBrain is Google's machine learning-based search ranking component, deployed in 2015, that uses word vector mathemati…
S
Semantic HTML
Semantic HTML is the practice of using HTML elements that convey meaning about the content they contain — not just visua…
Single-Page Application (SPA)
A single-page application (SPA) is a web application that loads a single HTML document and dynamically updates content u…
Schema Markup
Schema markup (also called structured data) is code added to your web pages — typically as JSON-LD in a `<script>` tag —…
Sass / SCSS
Sass (Syntactically Awesome Style Sheets) is a CSS preprocessor that extends standard CSS with programming features: var…
SSL / HTTPS
SSL (Secure Sockets Layer) — now technically its successor TLS (Transport Layer Security) — is an encryption protocol th…
SEO (Search Engine Optimisation)
SEO (Search Engine Optimisation) is the practice of improving a website's visibility in organic (unpaid) search engine r…
Structured Data & Schema Markup
Structured data (Schema markup) is formatted JSON-LD code added to web pages to help search engines understand the conte…
T
Tailwind CSS
Tailwind CSS is a utility-first CSS framework that provides low-level, single-purpose CSS classes — called utilities — t…
Twitter Card Meta Tags
Twitter Card meta tags are HTML `<meta>` elements placed in a page's `<head>` that instruct Twitter (now X) how to rende…
Topical Authority
Topical authority is a search engine's measure of how comprehensively and accurately a website covers a specific subject…
V
W
Website Builder
A website builder is a tool or platform that enables users to create websites without writing code from scratch. Website…
Wireframe
A wireframe is a low-fidelity, schematic representation of a web page or app screen that shows the structure and layout …
Web Design
Web design is the process of conceptualising, planning, and creating the visual layout, structure, and user experience o…
Web Accessibility (WCAG)
Web accessibility (often abbreviated a11y) is the practice of designing and building websites that can be used by everyo…
Web Typography
Web typography is the practice of selecting, sizing, and styling text on websites to ensure readability, visual hierarch…
Web Hosting
Web hosting is a service that stores your website's files (HTML, CSS, JavaScript, images, databases) on servers connecte…
WordPress
WordPress is a free, open-source content management system (CMS) that powers approximately 43% of all websites on the in…
What Is a Landing Page?
A landing page is a standalone web page designed with a single conversion objective — such as capturing a lead, selling …
Web Deployment
Web deployment is the process of transferring a web application or static site from a local development environment to a…
WebP Image Format
WebP is a modern raster image format developed by Google, introduced in 2010, that provides superior lossless and lossy …
Web Fonts Optimisation
Web fonts optimisation is the practice of reducing the performance cost of loading custom typefaces by controlling file …
Web Fonts
Web fonts are typefaces loaded from third-party sources (remote servers or local hosting) rather than relying on fonts p…
What Is favicon.ico?
A favicon.ico is a small square icon file, traditionally 16×16 or 32×32 pixels, that browsers display in tabs, bookmarks…
X
Put the theory to work
Generate production-ready Bootstrap 5 HTML using Canvas Builder. Describe any page and get clean code in ~3 minutes.
Start Building Free