Annotation threads in MADCOW 2.0.

madcow is a system for annotation of Web content, sup- porting the production and exploration of private and public annotations on text, images and videos in a Web page. Its design starts from the main requirement that the annotation activity must not disrupt the normal browsing of Web pages by a user. madcow allows interaction with the annotated portions of the page to provide access to the relative anno- tations. Conversely, the representation of the existing notes supports different forms of exploration of the Web page, and can become the starting point for further navigation over the Web. A uniform style of interaction has been adopted for creating and accessing annotations on text, images and videos, and some novel solutions have been introduced to cope with overlaps between the annotated portions. The annotation user experience is facilitated by enabling forms of in-place annotation and manipulation of both the anno- tated portion and the annotation content.