Sometimes a repository contains digitally signed packages. Signing is a method of ensuring packages haven't been tampered with, or forged. The programmer stamps each package with an ID that only she can create. This is done using a cryptographic key, the public component of which is offered for download and must be installed by end users.
Some apps have a "fullscreen" mode that will cause the title bar, GNOME menus and GNOME panel to temporarily disappear. This can be useful for maximizing screen real estate, or just working without backgrounddistractions. If the option is available it will show-up on the View menu.
Ubuntu offers the handy User Switcher applet at the top right of the desktop to switch between the desktop of two or more users. This is cleverer than it might first seem.
This is an oldie but worth mentioning in case you don't know. To kill the GUI, for whatever reason, such as a crash, hit Ctrl + Alt + Backspace. There's no warning dialog boxes when you do this - any open applications will be terminated, and data lost. You'll be returned to the GNOME
login screen, where you can login afresh.
If you're trying to fix a problem you might want to capture the output of a command for reproduction on a website forum, along with the command you typed to get the results. If you're working in a terminal window you can cut and paste, but what if you're working at a virtual console?
Sometimes if a USB memory stick or memory card stops working correctly, the best plan is to reformat it. To do this under Ubuntu, follow the steps below. Note that the instructions are extremely thorough - first the partition on the memory stick is deleted, then a new one is
created and subsequently formatted.
Wicd is an excellent swap-in replacement for NetworkManager. NetworkManager is the system software that sits in the notification area and handles network connections.
If you want to stop seeing the username/password prompt when you start Ubuntu, click System > Administration > Login Window. Then click the Security tab, and put a check in Enable Automatic Login.
To install a shared network printer in Ubuntu 8.10, such as one connected to another computer in your home or office, click System > Administration > Printing and click the NEW button in the toolbar (click NEW PRINTER if using Ubuntu 8.04). Then select the type of network printer you'd like to connect to across the network.
It's possible to switch between two or more keyboard layouts on the fly. This can be useful if you find yourself regularly typing in different languages.