HTML was first defined by Tim Berners-Lee in 1991 and has evolved through several versions. HTML5 and CSS3 are the next generation standards that will enhance the richness and interactivity of web content. HTML5 introduces new semantic tags and APIs for multimedia, geolocation, and offline storage. CSS3 includes features for rounded corners, drop shadows, columns, animations, and media queries for responsive design. While legacy browsers present challenges, HTML5 and CSS3 will improve the functionality of the mobile web and make the interface of the web comparable to native applications.