Things to know about the Dock in Leopard:

There are two icons on it that can't be moved
    • The Finder - located on the far left
    • The Trash - located on the far right


It is divided by a faint dashed line called the abbey road graphic which somewhat resembles the road in the Abbey Road graphic used on a Beatle album cover.

There are a lot of keyboard shortcuts to use with the Dock. Apple has an excellent list of these and ways to use the Dock more efficiently here.


Applications
All applications in the Dock stay on the left side.
     • They can be added by dragging them to the Dock from the Finder window.
     • They can be moved around by clicking and dragging them to the left or to the right where you want them.
     • They can be moved completely off the Dock by clicking and dragging them up and away from the Dock.
     • You launch an application by clicking once on its icon. No double-clicking necessary.
     • If you right-click or click and hold on an icon, it will give you a contextual menu with content that depends on the application.
     • If an application is open, it will automatically show up in the Dock and there will be a bright blip underneath it. Not a black triangle as in Tiger. To keep it there if it wasn't already, click and hold on it and select "Keep in Dock". Otherwise, it will disappear.
    • If no windows for an application are open, clicking on the already open app will usually bring up a new window.


 
Folders and Stacks
    • All folders & documents added to the Dock will stay on the right side of the dashed line.
    • Folders added to the Dock are immediately turned into Stacks. Stacks are a new feature that allow you to group a collection of Finder items and place them all together in the Dock for easy access.
    • Two Stacks are included in the Dock by default. They are your Downloads folder (new item) and your Documents folder.
    • To create a Stack, create a folder or have one ready, select two or more files from the Finder and drag them into that folder and then drag the folder to the area just to the left of the Trash.
    • To expand a Stack, click on the folder.
    • You can create as many Stacks as you want.
    • Depending on the number of items in a Stack, the Stack will either appear as a single column of items, as a fan or in a grid. You can set the default view by right-clicking on the Stack and setting the View Content as Fan, Grid, List or Automatic.
    • You can have the folder display as a Stack which means it will have the icon of the last item dropped into it or as a Folder which means it will always appear as a folder.
    • To add an item to a Stack, just drag it onto the Stack.
    • To remove an item from the Stack, click on the Stack to expand it, select the item and drag it out of the Stack.
    • Stacks sort items manually with the newest items usually appearing first. Folders sort them based on the default Name, Date Added, Date modified, etc unless you change that.
    • Selecting a folder within a Stack will open it in a new Finder window. Selecting a folder within a Folder will cause the content to appear in the Dock rather than in a separate Finder window.

       

Minimized Windows
    • Have too many windows open? Click on the yellow button in the top left corner of a window. This will minimize it and send it to the Dock and temporarily out of your way.
    • You can open a minimized window by clicking on it once.


The Trash
    • It is the next to the last place an item can be before being deleted. When you are ready, click and hold on its icon or go to Finder>Empty Trash to permanently delete its contents. This is a two-step process to hopefully prevent inadvertent deletion of files.
    • Going to Finder>Secure Empty Trash makes recovery of files almost impossible even with recovery software. Use with care, please.
    • To unmount any drives (thumb, external, CD or DVD, etc), drag it to the Trash. This will unmount it but not delete it.