This course introduces students to principles, programming languages, and specifications for developing distributed, web-based systems. The first part of the lecture deals with distributed systems, their characteristics and existing challenges in implementing them. We discuss also common architectures such as client-server and peer-to-peer. In the main part of this course we deal with technologies for supporting distribution. These technologies can be roughly assigned to three levels: technologies for ad hoc network programming (socket programming), technologies for structured communication (remote procedure calls) and middleware technologies. The latter level covers different approaches such as distributed object computing middleware and component middleware. We will discuss all these different implementations and in the lab you have time to test all the different approaches on real world examples. After introducing two applications of distributed computing: Cloud Computing and the World Wide Web, we will cover in the last part of the course topics that relate to the web application development such as data representations (e.g., XML, HTML), HTTP communication, JavaScript, CGI, Servlets, JSP.