Early Linux distributions were installed using sets of floppies but this has been abandoned by all major distributions. Nowadays most distributions offer CD and DVD sets with the vital packages on the first disc and less important packages on later ones. They usually also allow installation over a network after booting from either a set of floppies or a CD with only a small amount of data on it.
Still another mode of installation is to install on a powerful computer to use as a servers and to use less powerful machines (perhaps without hard drives, with less memory and slower CPUs) as thin clients over the network. Clients can boot over the network from the server and display results and pass information to the server where all the applications run. The clients can be ordinary PCs with the addition of a network bootloader on a drive or network interface controller; hard disk space and processor power can be offloaded onto the client machine if desired. The cost savings achieved by using thin clients can be invested in greater computing power or storage on the server.
In a Live CD setup, the computer boots the entire operating system from CD without first installing it on the computer's hard disk. Some distributions have a Live CD installer, where the computer boots the operating system from the disk, and then proceeds to install it onto the computer's hard disk, providing a seamless transition from the OS running from the CD to the OS running from the hard disk.
Both servers and personal computers that come with Linux already installed are available from vendors including Hewlett-Packard, Dell and System76.
On embedded devices, Linux is typically held in the device's firmware and may or may not be consumer-accessible.
Anaconda, one of the more popular installers, is used by Red Hat Enterprise Linux, Fedora and other distributions to simplify the installation process.
