I'm going to focus on one lightly concealed feature in OS X that gives extra power to experts but doesn't get in the way of beginners – and that's the Option key. This article focuses on OS X 10.8 Mountain Lion, released in July (see our review of the OS here), but most of what's written here also applies to earlier versions.
The Alt option
The Option key on a Mac keyboard is also labelled "Alt," and it's the same key as the Alt key on a Windows keyboard. But it does a lot more than the Alt key on a Windows machine. Whatever you're doing in OS X, try holding down the Option key when you do it, and chances are that you'll find a feature you never knew existed.
You can count on the Option key to add flexibility, power, or information to most OS X menus or keystrokes.
For example, say you've got three windows open in Safari or some other app and you want to minimise all three. You could click on the orange button on the title bar of each window in turn – or you could hold down the Option key and click on the orange button of one of the windows – and all three will minimise.
OS X gives you two other ways to accomplish the same trick. Click on the Window menu in Safari's top-line menu, then hold down the Option key; the "Minimise" menu item magically becomes "Minimise All." Also, if you're a true keyboard jockey, just press Option-Cmd-M to minimise all windows, instead of pressing Cmd-M to minimise just the current window.
"Save As…" saved
When Apple introduced OS X 10.7 Lion last year, it got rid of the "Save As..." item on the menus of many of Apple's own apps, such as TextEdit and Preview. Many expert users complained that Apple's replacement for Save As..., a new menu item called Duplicate..., added needless steps, even though it was probably a lot easier for beginner users to understand than the old Save As... option.
Apple seems to have listened, because in Mountain Lion, it quietly restored Save As..., but Apple hid the restored command behind the Option key. So, now, when you want Save As..., just hold down the Option key while clicking the File menu, or press Shift-Option-Cmd-S instead of Cmd-S. One advantage of Save As..., by the way, is that it makes it easy to save a document in a different format from its original. When the Save As... dialog appears, you can use a File Format drop-down menu to choose the format to save in.
The Preview app has an Export menu item that works exactly the way Save As... operates – it lets you save a copy of the file currently open, but under a new name and in a different format – but don't get the idea that the Option key doesn't hold hidden treasures in Preview. Whether you use the Export menu or the Save As... menu, you get to the same dialog box that lets you enter a filename and choose a format for saving the current file. In this dialog, you can click the Format button and choose from a drop-down menu listing six common formats, including JPEG, PDF, PNG, and TIFF.
If you're an expert user who wants a larger range of export formats, then – you guessed it – hold down the Option key when clicking the Format button, and you get a menu with seven additional formats, including GIF, BMP, and the formats used for both Windows and Mac icons.
Information is networking power
You can also use the Option key to get expert-level information that OS X otherwise hides. For example, hold down the Option key and click on the Wi-Fi button in the OS X menu bar. The drop-down will display statistics and other information about your current Wi-Fi connection.
If you're even moderately knowledgeable, this information can help you troubleshoot network problems, for example by telling you the hardware ID of the router or range extender to which your Mac is wirelessly connected. The same story applies to the battery icon on the menu bar: Hold down the Option key when you click the battery icon, and you'll get a report on whether your battery is in good or bad condition.
Or you can use the Option key to get – as you'd expect – more options. Hold down the Option key when clicking the volume indicator in the menubar, and you can select output and input devices with a couple of clicks, instead of going to System Preferences to do the same task.
Or you can use the Option key to save needless steps. For example, hold down the Option key while clicking the Apple menu at the upper left, and you can make the Shut Down or Restart items work immediately, without prompting you in a separate dialog. And in OS X's Launchpad, which shows all your apps in an iOS-style display of icons in a grid, hold down the Option key to make the icons jiggle and display an "X" icon that you can click on to delete the app.
Of course, there's a lot more to the Option key than the tips I've aired here. What have you discovered that I haven't described? Let us know in the comments section below, so the secrets of the Option key can be uncovered for everyone.