What is Astro?
Astro is an open-source web framework for building fast, content-focused websites. It renders pages to HTML at build time or on the server and ships no JavaScript to the browser by default, adding interactive components only where a page needs them through an approach called islands architecture.
How Astro works
Pages are written as .astro components: HTML plus a small script at the top that runs when the page is built. Astro can work as a static site generator, render pages on demand on a server, or mix both page by page.
Interactive parts can be written in React, Vue, Svelte or other UI frameworks. Each one becomes an island that loads its own JavaScript, while the rest of the page stays plain HTML.
Why Astro sites are fast
Less JavaScript means less work for the browser, which helps Core Web Vitals such as Interaction to Next Paint. Built pages can be served from a CDN, close to every visitor.
Astro and a CMS
Astro does not include a CMS. Content usually comes from Markdown files or a headless CMS such as Sanity, fetched when the site builds.
