The following lines were added (+) and removed (-):
# '''Main''' - preconfigured and your main Ubuntu support software# '''Main''' - preconfigured and your main Ubuntu support software repository# '''Universe''' - third-party free and open source software# '''Universe''' - third-party free and open source software === Add Repositories using Synaptic Package Manager ======Add Repositories using Synaptic Package Manager===Example: Repositories graphical interface (System -> Software and Updates)[[File:ubuntu-software-repositories01.jpg]]You can also add a repository without editing the sources.list file by defining additional source repository lists. You can place files in /etc/apt/sources.list.d The /etc/apt/sources.list.d directory provides a way to add sources.list entries in separate files. This seems unnecessarily "careful" however, some are more comfortable with this method.=== remove Repositories from the command line ===The repository can be removed also using the add-apt-repository command. sudo add-apt-repository --remove ppa:user/repository sudo apt-get update[http://ubuntuguide.org/wiki/Ubuntu_Trusty_Packages_and_Repositories Ubuntu Trusty Packages and Repositories] - focused on both Ubuntu and Kubuntu covering Unity, Gnome, and KDE. Extensive details on repository management. [http://ubuntuguide.org/wiki/Ubuntu_Trusty_Packages_and_Repositories Ubuntu Trusty Packages and Repositories] - focused on both Ubuntu and Kubuntu covering Unity, Gnome, and KDE. Extensive details on repository management. [https://help.ubuntu.com/community/Repositories/Ubuntu Ubuntu Community Help Wiki: Repositories/Ubuntu] - this information is not always current.