Sometimes when you install Ubuntu (a flavor of Linux) and then try to install new packages, you get this annoying message:

Media change: please insert the disc labeled
‘Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071016)’
in the drive ‘/cdrom/’ and press enter

To fix that message, click on

System->Administration->Software Sources and uncheck the “CD-ROM/DVD” option at the bottom of the menu:

Original post by Matt Cutts and software by Elliott Back