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The Ubuntu project is entirely committed to the principles of open source software development; people are encouraged to use open source software, improve it, and pass it on. This means that Ubuntu is and will always be free of charge.

You can find out more about the philosophy of free software <ulink url="http://www.gnu.org/philosophy/">here</ulink>.

Version and Release Numbers

What is Linux?

What is GNU?

When you run an application that requires root privileges, sudo will ask you to input your normal user password. This ensures that rogue applications cannot damage your system, and serves as a reminder that you are about to perform administrative actions which require you to be careful!

To use sudo when using the command line, simply type "sudo" before the command you wish to run. Sudo will then prompt you for your password.

Be careful when doing administrative tasks, you might damage your system!

All of the default graphical configuration tools in Ubuntu already use sudo, so they will prompt you for your password if needed.

Terminals

Starting the Terminal

To start <application>Terminal</application> choose <menuchoice><guimenu>Applications</guimenu><guimenuitem>Accessories</guimenuitem><guimenuitem>Terminal</guimenuitem></menuchoice> .

Common Commands

View Directories: - ls

Use the <keycombo><keycap>Ctrl</keycap><keycap>Alt</keycap><keycap>F1</keycap></keycombo> shortcut keys to switch to the first console.

To switch back to Desktop mode, use the <keycombo><keycap>Ctrl</keycap><keycap>Alt</keycap><keycap>F7</keycap></keycombo> shortcut keys.

All of the configurations and settings in Linux are saved in text files. Even though you most often can edit configurations through the graphical interface, you may occasionally have to edit them by hand. <application>Gedit</application> is the default Ubuntu text editor, which you can launch by clicking <menuchoice><guimenu>Applications</guimenu><guimenuitem>Accessories</guimenuitem><guimenuitem>Text Editor</guimenuitem></menuchoice> on the desktop menu system.

To add a new group, select the <guilabel>Groups</guilabel> tab and click <guilabel>Add group</guilabel>. Choose a name for the new group and, if you want, change the default value for the <guilabel>Group ID</guilabel>. If you try to allocate a <guilabel>Group ID</guilabel> that is in use, the system will warn you.

You can add users to the newly created group by selecting a user from the left menu and clicking on the <guilabel>Add</guilabel> button. Removing a user is as simple as adding one: select a user from the right menu then click <guilabel>Remove</guilabel>. When you are ready, click <guilabel>OK</guilabel> and the new group with its users, if inserted, will be created.

To edit the properties of a group, from within the <guilabel>Groups</guilabel> main window, choose a group name and click on the <guilabel>Properties</guilabel> button.

To remove a user or a group from the system, select the user or group you want to delete and click <guilabel>Delete</guilabel>.

After installing any new font, rebuild the font information files by typing the following at a terminal prompt:

RAR Archiver

Advanced Desktop Applets

For more information, visit the <ulink url="http://www.gdesklets.org/">gDesklets website</ulink>

Change my preferred email client to Mozilla Thunderbird

Restart GNOME without rebooting the computer

Save and close all open applications.

If you have a FAT32 filesystem, it is also safe to allow read-write access. To do this, change the value of <emphasis role="bold">umask</emphasis> to 0000.

The changes will take effect when the computer is restarted.

Run a system command automatically at startup

Insert the following line:

Save the file and exit.

Change default Operating System at boot

Make a backup of your boot configuration file, and open it in a text editor:

Find this line:

Replace with the following line:

default X_sequence

Permanently disable/enable boot-up services

This requires administrative privileges (see <xref linkend="root-and-sudo"/>).

Enter your password.

Tick/untick the services you want running, then click <guibutton>OK</guibutton> when done.

Hardware

Digital Cameras

Most USB digital cameras will be automatically detected by Ubuntu. Simply plug in and switch on your USB digital camera, Ubuntu will then ask you if you would like to import the photos from your camera. Click on <guibutton>Import</guibutton>, Ubuntu will then show you a preview of your photos. Choose a location to save your photos to, then click on <guibutton>Import</guibutton>, Ubuntu will then save your photos to your hard drive.

3D Graphic Cards

Introduction to 3D Video Acceleration

Most video hardware should work automatically with Ubuntu. However with some types of video hardware, 3D acceleration (which is needed by some games) will not be supported automatically. This section details how to get this working with some popular video hardware.

The first step is to find out whether 3D acceleration is working.

If 3D acceleration is working, the following will be displayed:<screen>direct rendering: Yes</screen>