html5 is the fifth major revision of Hypertext Markup Language (HTML), an application under the Standard Generalized Markup Language, the core language of the World Wide Web.
HTML 4.01 has changed a lot since 1999, and today, several of the elements that were deprecated in HTML 4.01 have been removed or redefined in HTML5. In order to better handle today’s Internet applications, HTML5 adds many new elements and features, such as: graphics drawing, multimedia content, better page structure, better form handling, and several api drag-and-drop elements, positioning, including web application caching, storage, web workers, and more.
tab (of a window) (computing)
descriptive