I have the Ubuntu 12.04 LTS Live CD, and I often install it on my friends computers and on my own frequently. So when I want to install it through a CD, I have to connect to the internet first? Wouldn't the operating system already be installed on the CD? I have no problem connecting to the internet. I just want to know why I have to in order to install it.
What says you have to connect to the internet?
If you mean the installer, that's so that you can have the system attempt to apply updated software automatically after installation of the base software. It'd then download and install the updates. If you check the box to update while installing then it forces the internet connection.
This does not reign true with the Minimal CD, however, as it does not contain the software for the OS and downloads it from the repositories.