Dock Preference Options
For more fine-tuning of the Dock, open the Dock pane of the System Preferences panel. This pane, shown in Figure 3.13, includes settings for adjusting the Dock's size and icon magnification and for making it disappear when not in use.
Figure 3.13 Configure your Dock to the size you want, or make it disappear when not in use.
Even if you choose the option to hide the Dock, it's not really gone; it reappears for your use when you bring your mouse cursor to the Dock's edge of your screen.
You can also shut off the animation effects that occur when document windows are minimized and stored in the Dock.
When you've made your selections, choose Quit (Command-Q) from the System Preferences application menu, or click the close button at the top of the window.