Glossary
Web Development Glossary: Terms Explained Simply (2026)
Plain-English explanations of the web development terms you will hear when building a website - from front-end to SEO, without the jargon.
- Front-end
- The part of a website users see and interact with: layout, colours, text, buttons. Built with HTML, CSS and JavaScript.
- Back-end
- The server-side code that powers a site: databases, logins, payments, business logic. PHP, Python and Node.js are common back-end languages.
- CMS
- Content Management System - software like WordPress that lets you create and edit content without code.
- Theme
- A pre-made design and layout system for a CMS. Custom themes are built to match a specific brand.
- Plugin
- An add-on that adds features to a CMS, such as forms, SEO tools or payment gateways.
- Responsive design
- A design that adapts to phone, tablet and desktop screens automatically.
- API
- Application Programming Interface - a way for different software to talk to each other, e.g. your site talking to a payment gateway.
- Hosting
- The service that stores your website files and serves them to visitors.
- Domain
- Your website address, e.g. cbws.in.
- SSL certificate
- Encryption for your site, shown by the padlock in browsers. Required for secure payments and good trust.
- CDN
- Content Delivery Network - servers around the world that serve your site faster to visitors everywhere.
- Schema / structured data
- Code that tells search engines what your content means (reviews, FAQs, prices), which can improve how you appear in results.
- Core Web Vitals
- Google's metrics for loading speed, responsiveness and visual stability - a ranking factor.
- Migrate / migration
- Moving a website (or its data) from one platform or host to another, with redirects planned to protect SEO.
- Redirect
- Automatically sending visitors from one URL to another, e.g. old pages to new ones after a rebuild.