In literature exist many links to translation of speech into sign language and links to gesturing with avatars. But the author cannot get any link to a visualization of background knowledge which deaf people are lacking. The author himself is hearing impaired. Therefore he knows of the importance of a good visualization of information needed to get the correct mental model. In this paper he claims that gesturing with avatars should be supplemented by visualization of background-knowledge. Based on the distinction between data, information and knowledge it is shown that efforts must be directed toward the visualization of complex, interlaced and situation-aware data to get the requirements of deaf people in a right manner.