The About window shows important legal information like the HUD3 License Agreement along with information about currently installed modules, the HUD3 version you are running, and allows you the option to uninstall or reinstall add-on components like the Windows TAPI dialer for integration with Outlook.
You can also uninstall and re-install HUD add-on modules like the Windows TAPI add-on and the Outlook add-on via the Components window accessible from Help --> about.