The lesson shows an high level and intuitive illustration of the operation principle of the video call in mobile phones, in particular focusing on solutions that allow to take advantage from radio wave communication and the voice flows and video codification techniques in bit of digital information (told through an intuitive comparison with the archery experience), with the aim of realizing the "magic" according to which in presence of critical scenarios (disturbance and radio noise on the wireless channel) the video can be sacrificed in favour of the voice quality, guaranteeing anyway the complete usability of the vocal communication. The student will understand how information communication works and how vocal information can survive (with a different priority), even tolerating the presence of transmission and receiving problems.