HTML5
HTML5 is the fifth and current major revision of HTML (HyperText Markup Language), the standard markup language for structuring content on the web, adding native support for audio, video, graphics, semantic structure, and offline/local…
Definition
HTML5 is the fifth and current major revision of HTML (HyperText Markup Language), the standard markup language for structuring content on the web, adding native support for audio, video, graphics, semantic structure, and offline/local storage without relying on browser plugins.
Overview
HTML5, finalized as a W3C recommendation in 2014 after years of development led by the WHATWG, was a significant leap from earlier HTML versions because it built in capabilities that previously required third-party plugins like Flash or Silverlight. Native `<video>` and `<audio>` elements, the `<canvas>` element for programmatic 2D graphics, and APIs for geolocation, drag-and-drop, and local storage meant developers could build rich, interactive experiences using only standard web technologies. HTML5 also introduced semantic elements — `<header>`, `<nav>`, `<article>`, `<section>`, `<footer>`, and others — that describe the meaning of content rather than just its visual layout, improving accessibility for screen readers and helping search engines understand page structure, which matters directly for SEO and Web Accessibility (a11y). Combined with CSS3 for styling and JavaScript for behavior, HTML5 completed the modern three-layer model of the web: structure, presentation, and behavior cleanly separated. Since HTML5 isn't formally versioned anymore — the WHATWG maintains it as a continuously evolving "living standard" — new elements and APIs are added incrementally rather than in discrete numbered releases, which is why developers today usually just say "HTML" rather than referring to a specific version number. HTML5's semantic and multimedia foundations underpin virtually every modern website and web app, including those built with frameworks like React that ultimately render down to standard HTML5 markup.
Key Features
- Native <video> and <audio> elements without plugins
- <canvas> element for programmatic 2D graphics and animation
- Semantic elements like <header>, <nav>, <article>, and <section>
- Built-in APIs for geolocation, drag-and-drop, and offline storage
- Improved form input types and validation attributes
- Maintained as a continuously evolving living standard by WHATWG