What are the differences between Desktop, Server, and Alternate Installs?

(just for the sake of doing it I have also included Ubuntu Netbook Edition here)

Similarities between all versions

• All versions support encryption of the home folder.
• All versions use the same application repositories, so that you can for instance install web and mail servers on Ubuntu Desktop or Ubuntu Desktop on a Ubuntu Server or Ubuntu Netbook system (by installing the ubuntu-desktop package), and any other combination.

Ubuntu Desktop

• The installer is called Ubiquity, which is written specifically to be a GUI installer for the Desktop/Live CD.
• Includes the Wubi installer for installation for Windows systems
• Installs the basic Ubuntu system, in addition to the ubuntu-desktop package and all its dependencies, including GNOME and various applications, such as Firefox and Empathy.
• You can try the system directly from the CD, and it has a graphical installation.

Ubuntu Server

• The installer is debian-installer, which is text based and is shared with Debian.
• It basically is just the base Ubuntu system, but during the installation you can optionally install services such as a web or mail server by using tasksel.
• Ubuntu Server does not include a graphical user interface so it does not install the applications included in the ubuntu-desktop package, such as GNOME.

Ubuntu Netbook

• Installs the basic Ubuntu system, in addition to the ubuntu-netbook package and all its dependencies. It also uses the Unity interface instead of the default GNOME interface.
• The installation method is very similar to Ubuntu Desktop

Ubuntu alternate installer

• The installer is debian-installer, which is text based and is shared with Debian.
• The alternate installer installs the ubuntu-desktop package, just as Ubuntu Desktop does.
• It is mostly intended for installing or upgrading Ubuntu on machines where this cannot be done in other ways. For instance, I had to use this CD when installing Ubuntu on my machine, because none of the LiveCDs would work.
• Allows setup of LVM and LUKS encrypted file systems
• Has an option for an "OEM Install", which allows you to install the OS but leave the personalization like username and password as part of the first boot.
• Option to install an LTSP Server.