With today's updates, the upcoming Ubuntu 12.04 LTS (Precise Pangolin) operating system received many new features and improvements, including the Privacy Settings, Video Lens for Unity and the HUD (Head-Up Display) system described in this article.
Originally introduced by Mark Shuttleworth last month, the Head-Up Display, or HUD for short, is some sort of add-on for the Unity interface allowing users to interact with application's menus by pressing the ALT key.
At the moment, HUD was introduced alongside the current menus placed on the Unity Panel, but in the end, the Head-Up Display system will entirely replace menus in Unity applications. However, this will most probably happen in Ubuntu 12.10.
HUD was developed by Canonical in-house during the last 18 months, and believe it or not it is here to revolutionize the Linux desktop.