While it’s surely the most important part of the GNOME Shell I left it at the last to give it more attention as it needs. I’m obviously talking about the Activities button, located in the upper left corner of the panel.
You can click upon it but you can also simply move the mouse pointer in the upper left corner of the screen to make it react as it was effectively pressed. In such case, a light blue animation (called ripple) is shown to help the user understand why the Activities screen was shown.
With the default keyboard configuration, the left Win key also works like to press the Activities button.
On the left side of the screen lies the Dash, a dock bar with the favorites shortcuts and all the running applications. In the opposite side, a partially visible bar offers its place for the Workspaces List. Just move the mouse pointer at the rightmost side of the screen and the workspaces list will slide out.
The bottom part of the screen will show the Notification and message tray, with all the pending messages and notification icons, if any, in the right corner. Please refer to the first part of the GNOME Shell exploration.
The top part of the screen will show the Windows and Applications picker, a selector which alternatively shows the visible windows of the running applications or the list of the available applications in the system.
You can click Applications picker to show the list of all the available applications or click the Windows picker to show the windows list of the running applications.
In the Applications list at first sight all the installed applications (with a proper shortcut in the menu) will be listed, regardless their category so that you can have a global view of all the applications.
Launching an application make it immediately visible in the foreground. After you launch one or more applications, the Windows list will show them in the Activities overview. All the running applications in the application list will have a white glow under their icon.
The right side of the applications list will show the categories of applications so that you can narrow your search by limiting the result to just one category. The categories list is not fixed but it does depend from the installed applications. New applications can then create new categories.
The search box above the categories list allows to search applications, shortcuts, resources (disks or bookmarks) or recent files by typing some letters of their names.
In the above image I’ve made a search for audio so various audio applications were returned. The applications search is always made in all the categories, so that the previously selected category will be ignored.
To start a search you don’t need to click the search box and then start to type, in every moment, in both windows or applications list, just to type some text and the search is immediately made. This is a great time saver if you know the name of what you’re searching, just open the Activities overview and type.
During every search, at the bottom of the screen, two buttons allow to make an external search on the web using Wikipedia or Google search engine. Both options will launch your default web browser and load the web page with the search results.
Further information can be found in: GNOME Shell Design.