Public institutions are part of a system within which various social relations take place. Their task is to bring order to society, enabling normal mutual life of people. They are the foundation of culture and civilization and the pledge of their permanence. One of the ways to accomplish this task is public work, as well as the continuous communication of information to the public. In both cases, they inevitably have to rely on different audiovisual systems such as: portable or installed sound systems, video presentation and video projection systems, audio-video conferencing systems and electronic voting and simultaneous interpretation systems.