OS X is an impressive technical achievement; many experts call it the best personal-computer operating system on earth. But beware its name.

The X is meant to be a Roman numeral, pronounced “ten.” Don’t say “oh ess ex.” You’ll get funny looks in public.

In any case, OS X Mountain Lion is the ninth major version of Apple’s Unix-based operating system. It’s got very little in common with the original Mac operating system, the one that saw Apple through the 1980s and 1990s. Apple dumped that in 2001, when CEO Steve Jobs decided it was time for a change. Apple had just spent too many years piling new features onto a software foundation originally poured in 1984. Programmers and customers complained of the “spaghetti code” the Mac OS had become.

On the other hand, underneath OS X’s classy, translucent desktop is Unix, the industrial-strength, rock-solid OS that drives many a Web site and university. It’s not new by any means; in fact, it’s decades old and has been polished by generations of programmers.


Apple no longer refers to its computer operating system as Mac OS X. Now it’s just “OS X,” without the “Mac.” Why? Apple says it’s to match up better with iOS, its operating system for the iPhone and iPad.

The Mac Becomes an iPad

If you could choose only one word to describe Apple’s overarching design goal in Lion and Mountain Lion, there’s no doubt about what it would be: iPad. That’s right. In this software, Apple has gone about as far as it could go in trying to turn the Mac into an iPad.

Two things made the iPad the fastest-selling electronic gadget in history. First, it’s so simple. No overlapping windows; every app runs full screen. No Save command; everything is autosaved. No files or folders. No menus. All your apps are in one place, the Home screen. To beginners, technophobes, and even old-timers, the iPad’s software represents a refreshing decluttering of the modern computer.

The second huge iPad sales point is that multitouch screen. You operate the whole thing by touching or dragging your fingers on the glass. For example, you cycle through screens by swiping. You zoom out on a map, photo, or Web page by pinching two fingers. You rotate a photo by twisting two fingers, and so on.

So Apple thought, if simplicity and touch gestures made the iPad a megahit, why can’t we do the same for the Mac?

And it set out to bring as many of the iPad’s features and as much of its personality to your Mac as possible. Today’s OS X features like Full Screen mode, Auto Save, and Launchpad are total iPad rip-offs; if Apple hadn’t stolen these features from itself, it would surely be suing for copyright infringement. In Mountain Lion, even the app names are the same as what’s on iOS: Reminders, Notes, Notification Center, Game Center, and so on.

Apple even brought over the whole multitouch thing to the Mac. No, you don’t touch the screen; you’d get screaming arm pain if you had to spend the day with your arm outstretched, manipulating tiny controls on a vertical surface three feet away. (The resulting ache actually has a name in the computer biz: gorilla arm.)

Instead, you use all those same iPad gestures and more, right on the surface of your laptop trackpad, Apple Magic Trackpad, or (if you have Apple’s Magic Mouse) the top surface of the mouse.

All of Mountain Lion’s big-ticket features are intended to work together. For example, suppose you’re looking at a document in full-screen view (feature #1). How are you supposed to switch to the next app? By swiping across the trackpad in the “next app” gesture (feature #2). Then you might pinch four fingers together (feature #3) to open Launchpad so you can open another program.

It’s a new way to work, for sure. And it’s optional. If it doesn’t float your boat, you can ignore all of it (full-screen, gestures, Launchpad, Auto Save). But you should at least make an informed decision—and this book, especially Chapter 0, should come in handy that way.


Truth is, Mountain Lion represents only a gentle continuation of the iPadization that began with OS X 10.7, known as Lion. Often in this book, you’ll read references to “Lion/Mountain Lion,” because they’re fundamentally the same software. Even so, there are enough nips, tucks, and improvements to justify the 20 bucks you just shelled out.

About This Book

You can’t get Mountain Lion on a disc or flash drive; it’s a download-only operating system. In other words, you don’t get a single page of printed instructions.

To find your way around, you’re expected to use Apple’s online help system. And as you’ll quickly discover, these help pages are tersely written, offer very little technical depth, lack useful examples, and provide no tutorials whatsoever. You can’t even mark your place, underline, or read them in the bathroom.

The purpose of this book, then, is to serve as the manual that should have accompanied OS X—version 10.8 in particular.

OS X Mountain Lion: The Missing Manual is designed to accommodate readers at every technical level. The primary discussions are written for advanced-beginner or intermediate Mac fans. But if you’re a Mac first-timer, miniature sidebar articles called Up To Speed provide the introductory information you need to understand the topic at hand. If you’re a Mac veteran, on the other hand, keep your eye out for similar shaded boxes called Power Users’ Clinic. They offer more technical tips, tricks, and shortcuts.

When you write a book like this, you do a lot of soul-searching about how much stuff to cover. Of course, a thinner book, or at least a thinner-looking one, is always preferable; plenty of readers are intimidated by a book that dwarfs the Tokyo White Pages.

On the other hand, Apple keeps adding features and rarely takes them away. So this book isn’t getting any thinner.

Even so, some chapters come with free downloadable appendixes—PDF documents, available on this book’s “Missing CD” page at—that go into further detail on some of the tweakiest features. (You’ll see references to them sprinkled throughout the book.)

Maybe this idea will save a few trees—and a few back muscles when you try to pick this book up.

About the Outline

OS X Mountain Lion: The Missing Manual is divided into six parts, each containing several chapters:

  • Part One covers everything you see on the screen when you turn on an OS X computer: the Dock, the Sidebar, Spotlight, Dashboard, Spaces, Mission Control, Launchpad, Time Machine, icons, windows, menus, scroll bars, the Trash, aliases, the menu, and so on.

  • Part Two is dedicated to the proposition that an operating system is little more than a launchpad for programs—the actual applications you use in your everyday work, such as email programs, Web browsers, word processors, graphics suites, and so on. These chapters describe how to work with applications in OS X—how to open them, switch among them, swap data between them, use them to create and open files, and control them using the AppleScript and Automator automation tools.

  • Part Three is an item-by-item discussion of the individual software nuggets that make up this operating system—the 29 panels of System Preferences, and the 50-some programs in your Applications and Utilities folders.

  • Part Four treads in more advanced territory. Networking, file sharing, and screen sharing are, of course, tasks OS X was born to do. These chapters cover all of the above, plus the prodigious visual talents of OS X (fonts, printing, graphics, handwriting recognition), and its multimedia gifts (sound, speech, movies).

  • Part Five covers all the Internet features of OS X, including the Mail email program and the Safari Web browser; Messages for instant messaging and audio or video chats; Internet sharing; Apple’s free, online iCloud services; and connecting to, and controlling, your Mac from across the wires—FTP, SSH, VPN, and so on.

  • Part Six. This book’s appendixes include guidance on installing this operating system; a troubleshooting handbook; a Windows-to-Mac dictionary (to help Windows refugees find the new locations of familiar features in OS X); and a thorough master list of all the keyboard shortcuts and trackpad/mouse gestures in Mountain Lion.


Throughout this book, and throughout the Missing Manual series, you’ll find sentences like this one: “Open the System folder→Libraries→Fonts folder.” That’s shorthand for a much longer instruction that directs you to open three nested folders in sequence, like this: “On your hard drive, you’ll find a folder called System. Open that. Inside the System folder window is a folder called Libraries; double-click to open it. Inside that folder is yet another one called Fonts. Double-click to open it, too.”

Similarly, this kind of arrow shorthand helps to simplify the business of choosing commands in menus, such as →Dock→Position on Left.


To get the most out of this book, visit Click the “Missing CD-ROM” link—and then this book’s title—to reveal a neat, organized, chapter-by-chapter list of the shareware and freeware mentioned in this book.

The Web site also offers corrections and updates to the book. (To see them, click the book’s title, and then click View/Submit Errata.) In fact, please submit such corrections and updates yourself! In an effort to keep the book as up to date and accurate as possible, each time O’Reilly prints more copies of this book, I’ll make any confirmed corrections you’ve suggested. I’ll also note such changes on the Web site so that you can mark important corrections into your own copy of the book, if you like. And I’ll keep the book current as Apple releases more Mac OS 10.8 updates.

The Very Basics

To use this book, and indeed to use a Macintosh computer, you need to know a few basics. This book assumes you’re familiar with a few terms and concepts:

  • Clicking. To click means to point the arrow cursor at something on the screen and then—without moving the cursor—press and release the clicker button on the mouse or trackpad. To double-click, of course, means to click twice in rapid succession, again without moving the cursor at all. And to drag means to move the cursor while holding down the button.

    When you’re told to ⌘-click something, you click while pressing the ⌘ key (which is next to the space bar). Shift-clicking, Option-clicking, and Control-clicking work the same way—just click while pressing the corresponding key.

    (There’s also right-clicking. That important topic is described in depth on The Complicated Story of the Function Keys.)

  • Menus. The menus are the words at the top of your screen: , File, Edit, and so on. Click one to make a list of commands appear.

    Some people click and release to open a menu and then, after reading the choices, click again on the one they want. Other people like to press the mouse button continuously after the initial click on the menu title, drag down the list to the desired command, and only then release the mouse button. Either method works fine.

  • Keyboard shortcuts. If you’re typing along in a burst of creative energy, it’s disruptive to have to grab the mouse to use a menu. That’s why many Mac fans prefer to trigger menu commands by pressing key combinations. For example, in word processors, you can press ⌘-B to produce a boldface word. When you read an instruction like “press ⌘-B,” start by pressing the ⌘ key, and then, while it’s down, type the letter B, and finally release both keys.


    You know what’s really nice? The keystroke to open the Preferences dialog box in every Apple program—Mail, Safari, iMovie, iPhoto, TextEdit, Preview, and on and on—is always the same: ⌘-comma. Better yet, that standard is catching on in other apps, too, like Word, Excel, and PowerPoint.

  • Gestures. A gesture is a swipe across your trackpad (on your laptop, or on an external Apple trackpad) or across the top surface of the Apple Magic Mouse. Gestures have been given huge importance in Mountain Lion. Appendix D contains a handy list of these gestures, or you can get a tutorial of life with gestures in Chapter 0.

  • Icons. The colorful inch-tall pictures that appear in your various desktop folders are the graphic symbols that represent each program, disk, and document on your computer. If you click an icon one time, it darkens, indicating that you’ve just highlighted or selected it. Now you’re ready to manipulate it by using, for example, a menu command.

  • Dialog boxes. See Figure I-1 for a tour of the onscreen elements you’ll frequently be asked to use, like checkboxes, radio buttons, tabs, and so on.

A few more tips on mastering the Mac keyboard appear at the beginning of Chapter 6. Otherwise, if you’ve mastered this much information, you have all the technical background you need to enjoy OS X Mountain Lion: The Missing Manual.

Knowing what you’re doing on the Mac often requires knowing what things are called. Here are some of the most common onscreen elements. They include checkboxes (turn on as many as you like) and radio buttons (only one can be turned on in each grouping).Pressing Return is usually the same as clicking the default button—the lower-right button that almost always means “OK, I’m done here.”
Figure I-1. Knowing what you’re doing on the Mac often requires knowing what things are called. Here are some of the most common onscreen elements. They include checkboxes (turn on as many as you like) and radio buttons (only one can be turned on in each grouping). Pressing Return is usually the same as clicking the default button—the lower-right button that almost always means “OK, I’m done here.”

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