Short definition

Frontend — the part of a website or web application that is rendered in the browser and used directly by visitors.

Also known as: front-end, front end.

The frontend is everything a visitor sees and uses in the browser: structure, layout, text, and interactions. The browser renders it on the visitor’s device, so its speed and reliability are immediately noticeable.

How does the frontend work?

HTML gives content meaning, CSS controls its presentation, and JavaScript adds behavior where needed. The browser combines them into the page. Every asset the visitor downloads matters: heavy scripts, unoptimized images, and render-blocking styles immediately affect the experience.

What does this mean for a small business?

Visitors use the frontend to find information, submit forms, and complete purchases. If those tasks are slow, unclear, or inaccessible, the website fails them regardless of how well its underlying systems work.

What should you watch for in a frontend?

  • start with semantic HTML and add JavaScript where needed;
  • ship as little code as the interface truly needs;
  • test keyboard navigation, focus order, and contrast;
  • measure loading performance on slow connections too;

How it relates to other website choices

The frontend can fetch dynamic data through an API. Frameworks such as Astro can keep the browser bundle small, while Core Web Vitals measure part of the resulting experience.