Inhaltsangabe:Abstract: For some years the Internet has been dominated by phrases like Web 2.0 and Ajax. The catchword Web 2.0, which was originally established by O Reilly at the first Web 2.0 conference in October 2004, not only describes a new way of perception and usage of the internet (e.g. social software like blogs, wikis, etc.), but also stands for more or less innovative techniques as for instance RSS or Ajax. The latter is a combination of techniques that have been available since the late 1990s, such as JavaScript, asynchronous requests and XML. However, the term Ajax only exists since Jesse James Garret introduced it in his article in February 2005. Since then Ajax has experienced a real hype. Google Mail, Google Maps or Flickr just serve as examples for the mass of applications that have to attribute their success substantially to Ajax. When it comes to web application development there has also been a lot of progress in the field of Ajax: Ajax frameworks of all kinds massively gained popularity and flooded the development community. From the biggest companies through to small development teams, almost everyone has published his own Ajax framework or library in the last two years. In the meantime there are far more than 150 different frameworks for various programming languages and diverse aims. Because of this uncontrolled growth of frameworks it is quite difficult to say which of those is most suitable for a specific project. There are two key questions that have to be considered in case of Ajax or Rich Internet Applications (RIAs) in general: How can Ajax significantly increase the business value of an application and how can it be applied productively? This thesis mainly focuses on the latter question by evaluating three Ajax frameworks of large companies with a strong background by means of an example application with respect to commercial applicability, productivity, performance as well as enhancement and adaptation possibilities. Furthermore this work discusses the technical limitations and problems of Ajax and provides an outlook on future developments in this area. As example application for the evaluation a web-based tracking system for public transportation is implemented. Each single vehicle is visualized on a street map according to its current position. By the implementation of this application with each of the three chosen Ajax frameworks their applicability, productivity and performance is illustrated as well as [...]