The frontend is the layer of a digital product the user sees and operates: the website or app interface running in the browser, built with HTML, CSS and JavaScript.
The frontend is responsible for everything you can touch: layout, typography, animations, forms, reactions to clicks. It is also the layer that determines perceived speed – the browser must download, parse and render frontend code before the user sees anything.
Modern frontends are built with frameworks (React, Vue, Svelte) or – for content sites – with approaches that generate static HTML (Astro, Next.js), combining developer comfort with maximum performance.
Why it matters for business: frontend quality translates directly into conversion (speed, fluidity), SEO (Core Web Vitals) and accessibility.