Multi-Tasking in Ubuntu
Ubuntu 12.04 includes a desktop interface that is a strong departure from previous versions. One of the most striking differences upon logging into the system is the launcher. The launcher is a vertical bar that, by default, resides along the left side of the screen. It is similar to the dock in Mac OS X and aims to make your user experience more efficient and intuitive.
Applications and Multi-Tasking
Various applications appear in the launcher by default. Other programs are installed in Ubuntu 12.04, but not all of them are present in the launcher (although they can be added). While icons on the desktop require the user to double-click to execute the application, icons in the launcher require only one click. After clicking on an application, its icon will begin to gradually change color. This behavior indicates that the computer is busy starting the program. Once the program is launched, an arrow will appear on the left side of the icon, as shown in the image to the left. In this example, a file explorer, Firefox, and terminal have all been launched.
If an application is already running, additional instances of the program can be started by using the middle mouse button. For example, a new Firefox window has been launched in the image below. Since two Firefox windows are now open, two arrows are on the left side of the Firefox icon in the launcher. Firefox is also the active program below, which is indicated by the arrow on the right side of the Firefox icon.
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