Although structurally similar, as Ubuntu is based on Debian, there are a few key differences:
- Ubuntu issues a CD that can be used both as a LiveCD and as an install medium. Debian has separate discs for this purpose. Debian's install-only disc is similar to the alternate install CD for Ubuntu (as both lack a live desktop environment).
- Debian does not have a single default interface, and issues CDs that include the packages for GNOME, KDE, and LXDE+Xfce. Ubuntu, strictly speaking, only uses GNOME by default. Releases that include other environments have different names, such as Kubuntu, Xubuntu, and Lubuntu.
- Debian does not have an official server variant or a kernel optimized for server use.
- Debian supports more platforms than Ubuntu. Ubuntu supports only i386, AMD64, and ARM (and formerly Itanium, Sparc and PowerPC). Debian supports all of these plus MIPS and S390. Older releases also supported 68k, Alpha, and HPPA.
- Ubuntu is a commercially-backed distribution, while Debian is a non-profit.