That vast empty area in the middle of the Mac’s display is known as the desktop. Like a real desk’s top, you’re welcome to place items on this desktop, though Apple encourages you to place your files in more appropriate places—your pictures in a Pictures folder and documents in a Documents folder, for example, or on Apple's online syncing and storage service, iCloud.
As you’re just starting out, I’ll plant this seed: Place files where they belong rather than dumping them on the desktop. (And yes, we’ll talk about file management eventually.) Not only is it difficult to find files when there are hundreds scattered across your screen, but overloading the desktop with certain kinds of files can actually slow down your Mac.
By default, at the bottom of the Mac’s display you see a long bar populated with a collection of icons. This is the Dock. By default the Dock holds these applications: Finder, Launchpad, Mission Control, Safari, Mail, Contacts, Calendar, Reminders, Notes, Messages, FaceTime, Photo Booth, iPhoto, iTunes, App Store, and System Preferences.
The Dock serves a couple of purposes. The first is that it acts as a way to quickly launch commonly used applications. Just click on an application and it either starts up (if it isn't already running), or the Mac switches to it (if it is). An application that is running (also known as an active application) will display a faint glow below the Dock’s application icon.
The majority of the Dock is taken up with applications. If you look closely, you’ll see a faint line near the right side of the Dock. The area to the left of that line is reserved for applications.
You can both add and remove applications from this area. To remove an application, just hold down the Option key on your keyboard (it’s two keys to the left or to the right of the spacebar) and drag the application out of the Dock. Its icon will disappear in a puff of virtual smoke. Don’t worry, if you do this you haven’t deleted the application from your Mac. Rather, you’ve just removed from the Dock the icon that represents that application. Basically you've removed the shortcut to the application, but the program still exists in the Mac's Applications folder.
When you launch an application that isn’t in the Dock, its icon will also appear in the Dock and have that faint glow beneath it indicating that it’s running. When you quit that application, it will disappear from the Dock.
If you’d like to add that or another application to the Dock in a more permanent way, just select it (from the Applications folder, for example) and drag it into this applications area. Its icon will appear where you place it and other icons will shift out of the way.
The Dock can also alert you to things that require your attention. For example, if iTunes can’t find a track you’ve asked it to play and iTunes isn’t the application you’re currently working with, the iTunes icon may bounce up and down in the Dock so that you’ll switch to it to learn about the problem it’s having. Additionally, some applications will show badges—red indicators planted on the application’s icon. Mail, for instance, will display a badge indicating the number of messages it’s received that you haven’t yet read.
And you can access some settings for active applications by clicking and holding on an application’s icon. For instance, if iTunes is running, you can click on its Dock icon and rate the currently playing song, pause playback, play the next or previous tracks, or shuffle songs. When Mail is active, you can ask it to retrieve new messages or you can choose to compose a new message.
To the right of the Dock’s faint line are, by default, two items. The first one—though it doesn’t look like it—represents a folder. Specifically, it’s a shortcut to the Downloads folder. When you download a file via Apple’s Safari Web browser, that file appears within this folder. Click on it in the Dock, and you see the folder’s contents.
These Dock folders can be confusing. By default, when such a folder contains just a few items and you click on it, the items pop-out in a fan list with the most recent items appearing at the top. When that folder has more than a few items in it and you click on it, those items appear in a grid. In a future column I’ll discuss customizing the Finder and talk about ways to make these folders show items in a more consistent way. For now, just understand that you may see items displayed in either a Fan or a Grid view. To launch a file in one of these views, just click on it.
Finally, at the right edge of the Dock is the Trash. When you want to delete something from your Mac, just click, hold, and drag it to the trash-can icon. If the Trash contains no files, it will change from a trash-empty icon to a stuff-in-the-trash icon and you’ll hear a dumped-something-in-the-trash sound effect. Like a real trash can, this one isn’t really empty until you do something to toss out the items in it. Rather it’s a holding area for items that you eventually intend to throw out for good and all. To really delete your files, click on the Finder menu and choose Empty Trash. A window will appear asking if you’re really sure you want to empty the Trash. Click the Empty Trash button to do exactly that. Otherwise, click Cancel and the items in the Trash will remain right where they are.
Once you’ve emptied the Trash, the items that were in it are, for all intents and purposes, gone. (There are some utilities that can retrieve them, but until you’re a little more up to speed on the ins and outs of the Mac, just assume they’re gone.) However, you can retrieve items if the Trash hasn’t yet been emptied. To do that, just click on the trash-can icon. A window will open that shows you the contents of the Trash. Drag the items you want to retrieve out of the trash to the desktop. You can now file them away.
This area to the right of the line isn’t intended only for the Downloads folder and Trash. If the area to the left of the line is for applications, this area is for everything but applications. If you have a folder you access routinely (the Applications folder, for example), you can drag it in here, and an icon representing it will appear. If you’ve minimized a window by clicking on its yellow button (something we’ll get to, I promise), it will appear in this area. If you have a file that you use over and over again—a text file that holds your personal diary, say—you can drop it in here as well.
There’s far more that you can do in the Finder—and we'll get to those things over time—but you’re now familiar with its major elements.
Next time: We look at windows—no, not Microsoft Windows. Rather, how windows work in OS X.