By far the easiest way to install Debian GNU/Linux is from a set of official Debian installation images. You can buy a set of CDs/DVDs or an USB stick from a vendor (see the CD vendors page). You may also download the installation images from a Debian mirror and make your own set, if you have a fast network connection and a CD/DVD burner. Or the modern way: write such image to an USB stick (see the Debian CD/DVD page and Debian CD FAQ for detailed instructions). If you have such installation media, and they are bootable on your machine, you can skip right to Chapitre 5, Démarrer le système d'installation. Much effort has been expended to ensure the most-used files are on the first DVD image, so that a basic desktop installation can be done with only the first DVD.

De plus, gardez à l'esprit que si le support d'installation que vous utilisez ne contient pas certains paquets, vous pourrez toujours les installer après, à partir de votre nouveau système Debian fraîchement installé. Si vous cherchez sur quelle image se trouve un paquet, vous pouvez utiliser https://cdimage-search.debian.org/.

If your machine doesn't support booting from optical media, but you do have a set of DVD, you can use an alternative strategy such as hard disk, net boot, or manually loading the kernel from the disc to initially boot the system installer. The files you need for booting by another means are also on the disc; the Debian network archive and folder organization on the disc are identical. So when archive file paths are given below for particular files you need for booting, look for those files in the same directories and subdirectories on your installation media.

Une fois l'installateur amorcé, il est capable d'obtenir tous les autres fichiers nécessaires à partir du disque.

Si vous n'avez pas de support d'installation, il sera nécessaire de télécharger les fichiers du système d'installation et de les placer sur un disque dur, un ordinateur connecté que vous pourrez utiliser pour amorcer l'installateur.