HTML5, the latest version of the HTML standard, introduces features that enhance support for rich media and web applications, making user interactions more efficient. It is built upon the success of HTML 4.01 and streamlines coding through new tags and multimedia elements while aiming for cross-browser compatibility as it continues to evolve. Key introductions include elements like <video>, <audio>, and <canvas>, while deprecated tags from previous versions must be replaced to ensure compatibility with modern browsers.