AMPHTML

AMP HTML, commonly referred to as amphtml, is an open-source subset of HTML designed for creating lightweight, fast-loading web pages on mobile devices. It is part of the Accelerated Mobile Pages (AMP) project, an initiative started by Google in collaboration with publishers to improve performance and user experience on the mobile web.

Pages authored in AMP HTML rely on the AMP runtime (amp.js) and a curated set of components, such as amp-img and amp-video. The framework enforces restrictions intended to keep render paths deterministic: JavaScript execution is restricted to AMP components, custom scripts are disallowed or sandboxed, and CSS is limited to inline styles with a total size cap. The page layout and interactivity are defined through the provided elements and attributes.

AMP pages can be served through the AMP Cache, a Google-operated CDN that validates and optimizes pages for fast delivery. Before publication, developers validate pages with the AMP Validator to confirm conformance with the AMP HTML specification.

Adoption and governance: Since its release in 2016, AMP HTML has been widely adopted by publishers, news outlets, and ecommerce sites to improve mobile performance and enhance visibility in search results that feature fast-loading content. The AMP Project is an open-source, community-driven effort governed by a coalition of contributors and industry stakeholders. Critics note ongoing concerns about control, dependency on Google's infrastructure, and the trade-offs between performance goals and developer flexibility.