Understanding the Dock

The Dock was one of the most revolutionary parts of the original Mac OS X desktop, and it remains one of the most noticeable aspects of the OS under version 10.3. If you want to master Mac OS X, you should learn to take full advantage of the Dock's capabilities.

The Dock provides you with information about, control over, and customization of Mac OS X and the applications and documents with which you work (see Figure 5.1). By default, the Dock appears at the bottom of the desktop, but you can control many aspects of its appearance and where it is located. You can also control how it works to a great degree.

Figure 5.1. The Dock is an essential part of Mac OS X; as you learn to use it, you will probably wonder how you ever got along without it.



The Dock was (and is) one of the most controversial parts of Mac OS X. Some Mac users love it, some hate it, and some just don't get it. I fall into the "love it" camp myself. Although the Dock takes a bit of getting used to, doing so will pay off for you in a big way.

The Dock is organized into two general sections; the application/document separation line, as shown in Figure 5.1, divides them. On the left side of this line, you see application icons. On the right side of the line, you see icons for documents, folders, minimized Finder or application windows, and the Trash/Eject icon.


In addition to applications or documents and folders, you might encounter another type of Dock icon. This type is called a dockling. Docklings are modules you can use to control applications or provide additional functionality on the Dock. Many docklings are available; some applications include docklings, whereas other applications consist entirely of a dockling. Docklings can be placed on either side of the Dock's dividing line. You will see an example of docklings later in the chapter.

The Dock performs the following functions:

  • Shows running applications? Whenever an application is running, you see its icon on the Dock. A small triangle is located at the bottom of every running application's icon (see Figure 5.1). The Dock also provides information about what is happening in open applications. For example, when you receive email, the Mail application's icon changes to indicate the number of messages you have received since you last read messages.

  • Enables you to open applications, folders, minimized windows, and documents quickly? You can open any item on the Dock by clicking its icon.

  • Enables you to quickly switch among open applications and windows? You can click an application's or window's icon on the Dock to move into it. You can also use the Tab key and Shift+Tab keyboard shortcuts to move among open applications.

  • Enables you to control an application and switch to any windows open in an application? When you hold down the Control key and click the icon of an open application, a pop-up menu appears. This menu lists commands as well as all the open windows related to that application; you can choose an item by selecting it from this menu.

  • Enables you to customize its appearance and function? You can store the icon for any item (applications, folders, and documents) on the Dock. You can also control how the Dock looks, including its size, whether it is always visible, where it is located, and so on.


The Dock menu for Classic applications does not list the windows open in that application. However, the other commands do appear on the menu.


When you open an application whose icon is not installed on the Dock, its Dock menu includes the Keep in Dock command. If you choose this, the icon is added to the Dock.

If you have used pre-Mac OS X versions of the Mac OS, you will see that the Dock is sort of a combination of the Apple menu, Application menu (and Application Switcher), and Control Strip. The Dock can be always available; you can customize its contents; and you can use it to quickly access any item on your Mac?these are all features that are similar to the Apple menu under Mac OS 9 and earlier. You can manage running applications using the Dock; this is similar to the Application menu. You can also open items with a single click from the Dock, just as you can with the Control Strip in previous versions of the Mac OS. Docklings, which are miniapplications stored on the Dock, are also similar to some items that appeared on the Control Strip in previous versions of the Mac OS.

When the Trash Is Not the Trash

Here is a question for you, "When is the Trash not the Trash?" If you have worked with Mac OS X before, you know the answer to this one! When you select an ejectable item, such as a CD or a mounted network volume, the Trash icon on the Dock becomes the Eject icon. When you drag an ejectable item onto this icon, it is ejected from your Mac. This makes more sense than dragging something onto the Trash to eject it. If you have ever seen a new user freak when you tell him to remove something by dragging it to the Trash under Mac OS 9 or earlier, you understand why this is a good thing. Dragging something onto the Trash to eject it was always one of the most counterintuitive aspects of the Mac OS.

    Part I: Mac OS X: Exploring the Core
    Part III: Mac OS X: Living the Digital Life