Glossary
The terms behind the work.
Plain-English definitions of the web development, performance, WordPress, and SEO concepts we build around, from Core Web Vitals and technical SEO to headless architecture and AI search. Written for the people who hire us rather than for other engineers: every entry says what the term means, why it matters commercially, and where the trade-offs live.
Performance
Core Web Vitals and the mechanics of a fast site: what the metrics measure, what slows pages down, and which fixes actually move them.
- Core Web Vitals Google's three user-experience metrics: LCP for loading, INP for responsiveness, and CLS for visual stability. Together they feed directly into search rankings.
- Critical CSS The minimal styles needed to render the visible top of a page, inlined into the HTML so first paint doesn't wait on external stylesheets.
- Cumulative Layout Shift (CLS) A Core Web Vital that measures how much a page's content unexpectedly shifts while it loads. Lower scores mean a calmer, more stable reading experience.
- Interaction to Next Paint (INP) A Core Web Vital that measures how quickly a page visually responds to taps, clicks, and keypresses. It replaced First Input Delay in March 2024.
- Largest Contentful Paint (LCP) A Core Web Vital measuring how long the largest visible element, usually a hero image or headline, takes to render. The clearest proxy for perceived load speed.
- Lazy Loading Deferring images, video, and other assets until they're about to scroll into view, so the initial page load carries only what the visitor can see.
- Render-Blocking Resources CSS and JavaScript the browser must download and process before it can paint anything, holding the page blank and inflating load metrics.
- Time to First Byte (TTFB) The time between a browser requesting a page and receiving the first byte back. It reflects server and hosting speed, and caps how fast everything else loads.
Web Development
Frameworks, architectures, and build approaches: the vocabulary of how modern sites and web applications are put together.
- Astro A modern web framework that ships static HTML with minimal JavaScript by default, giving content-driven sites a fast, SEO-friendly foundation.
- Headless CMS A content management system that stores content and delivers it through an API, decoupled from the front-end that presents it.
- Headless Commerce An ecommerce architecture where the storefront is a custom front end talking to Shopify or WooCommerce through APIs instead of the platform's built-in theme.
- Jamstack An architecture for fast, secure sites built on pre-rendered markup, JavaScript, and APIs, decoupling the front-end from servers and databases.
- Progressive Web App (PWA) A website that installs and behaves like a native app (home-screen icon, offline support, push notifications) while remaining a single web codebase.
- Static Site Generation (SSG) Building a website into plain HTML files ahead of time, so pages serve instantly from a CDN instead of being assembled by a server on every request.
- Website Migration Moving a site between platforms, domains, or architectures while preserving its content, URLs, and search equity. Done well, invisible; done badly, expensive.
WordPress
The terms that decide whether a WordPress site stays healthy: what accumulates, what breaks, and what modernization actually fixes.
- Plugin Bloat The accumulated weight of too many WordPress plugins: overlapping features, competing scripts, security surface, and a site that gets slower every install.
- WordPress Page Builder A drag-and-drop WordPress plugin, such as Elementor or Divi, for building pages visually. Convenient to edit, but often the source of slow, bloated sites.
- WordPress-to-Astro Migration Rebuilding a WordPress site on the Astro framework to ship static, near-instant pages while preserving the content and editorial workflow.
SEO
Technical and local search, structured data, and the newer AI-driven surfaces: how search engines and language models find, understand, and cite a site.
- AI Overviews Google's AI-generated answer box that synthesises search results into a written response, citing a handful of sources above the traditional links.
- Canonical URL The single authoritative address you declare for a page's content, so search engines consolidate duplicates and rank one URL instead of splitting signals.
- Crawl Budget The finite attention a search engine spends crawling your site. Wasted on duplicates, redirect chains, or junk URLs, it delays the pages that matter.
- Generative Engine Optimization GEO: optimising content and site structure so AI search surfaces (ChatGPT, Gemini, AI Overviews) can find, understand, and cite your business as an answer.
- Google Core Update A broad, periodic update to Google's ranking systems that can sharply shift visibility, rewarding helpful content and demoting thin or manipulative pages.
- Internal Linking The deliberate structure of links between your own pages, which distributes authority, guides visitors, and tells search engines what matters most.
- Local SEO Optimising a business to appear in location-based searches and map results: the work that puts you in front of nearby customers who are ready to buy.
- Structured Data (Schema Markup) Code added to a page that tells search engines what its content means, making it eligible for rich results like FAQs, reviews, and breadcrumbs.
- Technical SEO Optimising a site's infrastructure (crawlability, indexation, speed, structured data, architecture) so search engines can find, understand, and rank it.
Strategy
The engagement-level concepts behind the engineering: how we evaluate systems and where the real costs hide.
- Conversion Rate Optimisation (CRO) Improving the share of visitors who take a desired action, whether buying, enquiring, or signing up, through testing, clearer design, and faster pages.
- Technical Debt The accumulated cost of past shortcuts in a codebase or platform. Like interest, it compounds: every change gets slower and riskier until the debt is paid down.
- Topical Authority The depth and breadth of genuinely useful content a site has on a subject. Search engines reward comprehensive coverage over shallow, one-off pages.