Newbies of Ubuntu/Kubuntu/Edubuntu will be confused by the name of her official released CDs – Desktop Live CD, Alternate CD and Server CD. Why she makes these different CDs?
Desktop Live CD
Live CD allows user to boot it from CD-ROM and experience the power of Linux. Live CD is a complete operating system that running from CD. You can use it for testing hardwares and/or softwares compatibilty. You can use it to taste the new version of the distribution. You can use it for internet kiosks or libraries.
You can install any software on the Live CD. Once you reboot or switch off, the change will be lost. Ubuntu Desktop Live CD provides the most common features to end-users, especially for newcomers. It is very easy to use and/or install. If you have no experience in Linux, you can install Ubuntu via the Live CD in a few steps. You can choose the default setting if you are in doubt. It requires more memory compare with Alternate CD.
In addition, you can install Ubuntu by Live CD on a Windows system via Wubi. Wubi allows you to install Ubuntu in Windows system as a file. You can uninstall it just like other Windows softwares.
Alternate CD
Unlike Live CD, Alternate CD is a text mode installer. It requires an experienced Linux user to operate. It provides more drivers, such as FakeRAID, software RAID and some other drivers and features. You can also choose LVM and encrytped directory too. It is more flexible and powerful compare with Live CD. The final product is a graphical desktop environment. It can install for a lesser memory machine, thanks to the text mode installer.
Server CD
It is a text mode installer and similar to Alternate CD. You can choose some common servers to install, such as LAMP, mail server, DNS, SQL server and File Server. The servers that you have chosen are almost configured but some of them need to be tuned for different usage. It is targeted to experienced Linux users. The final product is a command line environment.
Conclusion
Ubuntu makes 3 different CDs in order to keep it fit in a 700MB CD and targeted to different users. Although it may cause confusion, it is a good idea for different market and user.
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The desktop CD allows you to try Ubuntu without changing your computer at all, and at your option to install it permanently later. This type of CD is what most people will want to use. You will need at least 192MB of RAM to install from this CD.
Server install CD
The server install CD allows you to install Ubuntu permanently on a computer.
Alternate install CD
The alternate install CD allows you to perform certain specialist installations of Ubuntu. It provides for the following situations:
* creating pre-configured OEM systems;
* setting up automated deployments;
* upgrading from older installations without network access;
* LVM and/or RAID partitioning;
* installs on systems with less than about 192MB of RAM.
Live CD可以免安装体验 也可以用于网络诊断 比较方便
Live CD也可以用于在windows引导不了时做一些工作
Live CD还可以用于备份系统 还可以用于安装gentoo lfs等发行版
Live CD能干嘛 就看你的想象力了
实乃是居家旅行 走亲访友 杀人越货之必备良药
单纯的安装角度来看
alternate install cd是首选 占用资源小 兼容性好 速度快 定制性相对强
ubuntu 发布的linux里面有一个非常具有迷惑性的版本-desktop。因为有一套server，所以desktop很容易从字面上被理解成桌面版。而这样理解的人通常会弄不明白剩下那个alternate是什么东西。
其实desktop是Live CD的名字，也就是刻录在光盘上运行的Linux。是一套已经装好的系统。把它烧录到光盘上放进光驱就可以直接运行这套完整的linux。当然你也可以在运行之后把它“安装”到硬盘上，而这样的安装更像是一种拷贝或者还原，类似ghost。
真正意义上正统的安装版本则是alternate，它是由许多deb包组成的。可以详细的制定安装内容。是正宗的硬盘安装版。
这两个版本还有一些速度上的区别。
因为类似系统还原，desktop的安装速度较快。而alternate正式的安装相比之下会慢一些。
而运行的时候恰好相反：desktop因为是既成的，可能会缺少对应软件环境的适应性，所以和灵活指定及安装的alternate相比会慢一些。
desktopCD安装前可以看到基本界面和试用(liveCD功能),
alternate面向安装个性化需求更大的更专业一点点的用户.
desktop和alternate都有基本的软件包,要更多的软件包只要修改合适的源下载也是很快的.
desktop是一个live cd ,只用于桌面系统，也可以在LiveCD状态下安装。
alternate是标准的安装CD。包含了一些桌面程序，可以用高级安装模式安装，在安装时可以划分分区。也可以当作Server来用，不过一些Server 程序要自己通过网络来安装
Alternate安装过程会有高级分区以及grub安装选项,Desktop没有.
alternate既能安装desktop也能安装server
desktop是一个live cd ，在桌面环境里面 以向导的方式引导安装
live CD 就是把安装好的软件放到光盘中， 安装时就把其上的内容复制到硬盘再简单配置就行了。
alternate CD上放的DEB的软件包，安装时要解压、配置
只有在机子硬件配置很低时用 live CD安装较慢，其余都比alternate的要快。
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The Desktop CD Install installs from within a nice graphical interface, and I believe previously had no repository on the CD, it just copies the files across from the cd and eats up memory because it is running a live version as it installs. Excellent if you do not want to install via a menu driven intreface or a command line system.
The Alternative CD installs in a command line environment or menu driven interface, is easy to customize as you go along if you know what you are doing, making it easy to install on low system requirement and does not cause many of the failed installations as the Desktop CD. The alternative CD has a repository on the CD.
The Server CD does not install any desktop environment, such as kde or gnome, and installs a kernel that is less responsive to user inputs (via mouse or keyboard) and is more responsive to disk activity. IE it installs a slightly different kernel. With a server cd if you want a desktop you have to install it via the repositories by apt-get install ubuntu-desktop. The server cd has repository sources on the CD.
That I think are the main diffrences.