With "Installed Programs" module Total Uninstall analyzes the installed program and creates the installation log. This is used to do a complete uninstall even without the help of the provided built-in uninstaller.
With "Monitored Programs" module it helps to monitor any changes made to your system during the installation of a new program. It allows you to perform a complete uninstall without having to rely on the supplied built-in uninstaller, which can leave files or changes behind.