Elements of the desktop
  1. Apple menu () - Access Software Update, System Preferences, Sleep, Shut Down, and more.
  2. Application menu - Contains menus for the application you're currently using. The name of the application appears in bold next to the Apple menu.
  3. Menu bar - Contains the Apple menu, active application menu, status menus, menu bar extras and the Spotlight icon.
  4. Status menu - Shows the status of your computer or gives you quick access to certain features—for example, you can quickly turn on Wi-Fi, turn off Bluetooth, or mute your computer's volume.
  5. Spotlight icon - Click it to bring up the Spotlight search field, where you can search for anything on your Mac.
  6. Desktop - This is where your applications' windows will appear. You can add more desktops using Spaces, see this article.
  7. The Dock - Quick access to your most frequently used applications, folders, and files. With a single click the application, folder, or file opens.

Organize your desktop files and folder
If you download and create files on your desktop, it may become cluttered after some time. You can organize your desktop files by grouping them into folders on your desktop. Just select the items you want to group, Control-click one of the selected items, and then choose "New Folder with Selection" from the shortcut menu. Then enter a name for the folder. All of the selected files will be grouped in the new folder.

Customize your desktop
You can change the size of icons, arrange them in a grid, and set other preferences for items on your desktop by changing the view options on your desktop. To change your desktop view options, click the desktop, and then choose View > Show View Options from menu bar. You can try the different settings to see which ones you like—you will immediately see the effects of your changes.

Change your background
You can change the picture that's displayed on your Mac's desktop. You can choose one of the desktop pictures that comes with your Mac, a solid color, or one of your own pictures.
  1. Click the Launchpad icon (or System Preferences icon for Mac OS X v10.6) in the Dock.
  2. Click Desktop & Screen Saver, and then click Desktop.
  3. Select the picture you want in the box on the right.
To select the kind of desktop picture you want to use, do one of the following:
  1. To use an image that come with your Mac, select a folder under the Apple section.
  2. To use a solid color, select "Solid Colors" under the Apple section.
  3. To use your own picture, select the Picture folder under "Folders," if the picture you want is stored in your Pictures folder. If your image is in another folder, click the Add button (+), then find and select the folder that your picture is in. Then click Choose.

Change what's displayed on your desktop
You use Finder preferences to choose what type of items appear on your desktop.
Finder preferences window in OS X Lion
  1. Click the desktop.
  2. Choose Finder > Preferences, and then click General.
  3. In the "Show these items on the desktop" section, select the items you want to appear on your desktop, such as hard disks and external disks.