sentences:  HTML5 is intended to subsume not only HTML 4 but also XHTML 1 and DOM Level 2 HTML.HTML5 includes detailed processing models to encourage more interoperable implementations; it extends, improves and rationalizes the markup available for documents and introduces markup and application programming interfaces (APIs) for complex web applications.For the same reasons, HTML5 is also a candidate for cross-platform mobile applications, because it includes features designed with low-powered devices in mind.