The goal for this master thesis was to investigate the possibility of using an existing web server and modify it so it can be used in ABB controllers. The work has resulted in two different versions of a web server. The basic functionality is the same for both versions. The web servers are able to present a number of controller-related information. For example: hardware, which control programs that are executing in the controller, information about the firmware, and also system information like heap memory usage. It can also be used for changing different parameters. The two versions use different techniques for presenting the information. They are also implemented in different ways. The first version has a more user-friendly interface but ...