This section will help you determine which different media types you can use to install Debian. There is a whole chapter devoted to media, Chapter 4, Obtaining System Installation Media, which lists the advantages and disadvantages of each media type. You may want to refer back to this page once you reach that section.
USB flash disks a.k.a. USB memory sticks have become a commonly used
and cheap storage device. Most modern computer systems also allow
debian-installer from such a stick. Many modern computer systems, in
particular netbooks and thin laptops, do not have an optical drive
anymore at all and booting from USB media is the standard way of
installing a new operating system on them.
The network can be used during the installation to retrieve files needed for the installation. Whether the network is used or not depends on the installation method you choose and your answers to certain questions that will be asked during the installation. The installation system supports most types of network connections (including PPPoE, but not ISDN or PPP), via either HTTP or FTP. After the installation is completed, you can also configure your system to use ISDN and PPP.
You can also boot the installation system over the network without needing any local media like CDs/DVDs or USB sticks. If you already have a netboot-infrastructure available (i.e. you are already running DHCP and TFTP services in your network), this allows an easy and fast deployment of a large number of machines. Setting up the necessary infrastructure requires a certain level of technical experience, so this is not recommended for novice users.
Diskless installation, using network booting from a local area network and NFS-mounting of all local filesystems, is another option.
Booting the installation system directly from a hard disk is another option for many architectures. This will require some other operating system to load the installer onto the hard disk. This method is only recommended for special cases when no other installation method is available.
If you are running another Unix-like system, you could use it to install
Debian GNU/Linux without using the
debian-installer described in the rest of this
manual. This kind of install may be useful for users with otherwise
unsupported hardware or on hosts which can't afford downtime. If you
are interested in this technique, skip to the Section D.3, “Installing Debian GNU/Linux from a Unix/Linux System”. This installation method is only recommended
for advanced users when no other installation method is available.