I copied and pasted most of this from the old thread because it was open source.

About Ubuntu
Taken from Wikipedia, the free encyclopedia
Ubuntu (pronounced /ʊˈbʊntuː/ oo-boon-too) is a computer operating system based on the Debian GNU/Linux distribution and distributed as free and open source software. It is named after the Southern African philosophy of Ubuntu ("humanity towards others").
With an estimated global usage of more than 12 million users, Ubuntu is designed primarily for desktop use, although netbook and server editions exist as well. Web statistics suggest that Ubuntu's share of Linux desktop usage is about 50%, and indicate upward trending usage as a web server.
Ubuntu is sponsored by the UK-based company Canonical Ltd., owned by South African entrepreneur Mark Shuttleworth. Canonical generates revenue by selling technical support and services tied to Ubuntu, while the OS itself is entirely free of charge.
(Ubuntu's interface. The entire UI is built with the GNOME 2 and UNITY shell and can be customized greatly.Click here for full size image)(Ubuntu Oneiric will use stuffty Gnome 3 :C)
Ubuntu is composed of many software packages, of which the vast majority are distributed under a free software license, making an exception only for some proprietary hardware drivers. The main license used is the GNU General Public License (GNU GPL) which, along with the GNU Lesser General Public License (GNU LGPL), explicitly declares that users are free to run, copy, distribute, study, change, develop and improve the software. On the other hand, there is also proprietary software available that can run on Ubuntu. Ubuntu focuses on usability, security and stability. The Ubiquity installer allows Ubuntu to be installed to the hard disk from within the Live CD environment, without the need for restarting the computer prior to installation. Ubuntu also emphasizes accessibility and internationalization to reach as many people as possible. Beginning with 5.04, UTF-8 became the default character encoding, which allows for support of a variety of non-Roman scripts. As a security feature, the sudo tool is used to assign temporary privileges for performing administrative tasks, allowing the root account to remain locked, and preventing inexperienced users from inadvertently making catastrophic system changes or opening security holes. PolicyKit is also being widely implemented into the desktop to further harden the system through the principle of least privilege.
Ubuntu comes installed with a wide range of software that includes OpenOffice, Firefox, Empathy (Pidgin in versions before 9.10), Transmission, GIMP (in versions prior to 10.04), and several lightweight games (such as Sudoku and chess). Additional software that is not installed by default can be downloaded and installed using the Ubuntu Software Center or the package manager Synaptic, which come pre-installed. Ubuntu allows networking ports to be closed using its firewall, with customized port selection available. End-users can install Gufw (GUI for Uncomplicated Firewall) and keep it enabled. GNOME (the current default desktop) offers support for more than 46 languages. Ubuntu can also run many programs designed for Microsoft Windows (such as Microsoft Office), through Wine or using a Virtual Machine (such as VMware Workstation or VirtualBox). For the upcoming 11.04 release, Canonical intends to drop the GNOME Shell as the default window manager in favor of Unity, a graphical interface it first developed for the netbook edition of Ubuntu.
Update: Ubuntu 11 is out and doesn't use GNOME 2 anymore.
Compiz
Compiz is a system which adds a load of neat graphical effects that are customizable to your liking. Compiz is normally built into Ubuntu and can be activated by installing the latest video drivers for your graphics card, and downloading CompizConfig Settings Manager. This can be done by running the following command in Terminal:
sudo apt-get install compizconfig-settings-manager
After this, use the CompizConfig Settings Manager to change the settings for the cube. When you're finished, activate the cube by holding CTRL + ALT and clicking and dragging the mouse. You can also drag windows across sides by simply pulling them over the edge of the screen, and you can quickly flip between sides by holding CTRL + ALT and pressing the left and right arrow keys.
A final note - Compiz requires your graphics card's drivers. Open source ones (xorg) won't work.
I really want this now. Can I have it?Hell yes, you sure can. As stated above, Ubuntu is 100% free OS and always will be. But you still need to choose what package you want for it.
DESKTOP/LAPTOP EDITION - Supports 32-bit and 64-bit desktop and laptop PCs. You can get the most recent version (11.04) and install it on a partition only. If you want to test Ubuntu or install it with Wubi, you can get the Long-Term Support version, 10.04 LTS (Lucid Lynx).
NETBOOK REMIX - Specifically designed for Netbooks. This can also be ran on a desktop or laptop, but I'm not sure why you'd want to.
WANT TO JUST GIVE IT A TEST RUN?Head to their website, download the .ISO file and burn it to a disc. When you boot up with the disc inserted, Ubuntu's menu will load up and ask if you want to either A) Install the OS, or B) run it from the Live CD. If you want to try it out before you install it, run it from the CD. This makes it so that your hard drive will not be touched, and the entire operating system will be temporarily ran off of the Ubuntu disc. Keep in mind though - this is only for playing around. You can't save anything because there is no storage space you can save it to.
WANT TO KEEP WINDOWS AS WELL?Insert the disc while the computer is running. When promted, run Autorun.exe and Ubuntu will ask if you want to install Wubi, which allows you to run Ubuntu along side of Windows. This means that every time you turn your PC on it will ask you if you want to use Ubuntu or Windows! What a brilliant system!
OTHER VERSIONS OF UBUNTU WITH DIFFERENT SHELLS, YOU SAY?Yes. There are currently plenty of distributions of Ubuntu, renamed and developed by other communities. Click a logo to go there!



DiscussionHey, it's a megathread. Discuss everything related to Ubuntu, Debian, Linux distros and Open-Source software here. Try to keep the topic on track.
All other information can be learned from:http://www.ubuntu.com/
Bonus: This entire thread was typed up on Ubuntu 10.04 LTS! :D
Common problems and fixes!
Q.I don't have any drivers! How do I get them?
A.System > Administration > Additional Drivers
Q.How do I run Windows stuff?
A.Wine. Search it in the software center.
/**
*Source Code
*/
sudo rm -f /