Nowadays, Rich Internet Applications (RIAs) have emerged as a new generation of Internet applications. This approach combines the advantages of desktops and Web applications incorporating behaviors and features of desktop applications such as animations and multimediacontent. This paper presents an overview of multimedia support into JavaScript-based Frameworks for developing RIAs. The most popular JavaScript-based frameworks are analyzed and a case study is presented taking as reference the development of a Web application with similar functionality that provides a site such as YouTube in terms of video playback.