package management - How do I enable the "partner" repository?

I keep seeing places refer to the "partner" repository as a place I can get software, how can I enable this repository? Please specify how to do this graphically and via command line.

GUI Way:

Click on the ubuntu button, then search for "Software Sources" (or "Software & Updates" on Ubuntu 16.04+) and go to the "Other Software" tab.

Command Line Way:

• Open the sources.list file: gksudo gedit /etc/apt/sources.list (or with the command line editor of your choice, sudo nano /etc/apt/sources.list would use nano on the command line without a GUI)



• Add the partner repositories by removing the # in front of the following lines (maverick is the version of your Ubuntu installation, it may differ, so use the codename of the release you are using instead of 'maverick'. If you're not sure run lsb_release -c to find out.)

  
  
  

  # deb http://archive.canonical.com/ubuntu maverick partner
  # deb-src http://archive.canonical.com/ubuntu maverick partner
  

• Save and Close.



• Resynchronize the package index files from their sources: sudo apt-get update




• Official documentation for reference