Mac OS X 10.6 (Snow Leopard)

Snow Leopard is version 10.6 of the Macintosh operating system and the successor to Leopard (version 10.5). Apple calls Snow Leopard a “minor” update to OS X, but even so it features loads of tweaks and new features (see below).

I purchased my copy of Snow Leopard last week and got around to installing it this weekend. Because the new operating system includes several changes that might make older applications not work as expected, I recommend that you use SnowChecker, a free application available here, to check your installed applications’ compatibility before performing the upgrade.

The installation took about an hour and performed a seamless upgrade from Leopard to Snow Leopard, keeping all my applications and settings intact (just as you’d expect from Mac OS X), even my custom-compiled versions of PHP and MySQL.

After the first boot the Mac OS X welcome video was played (Snow Leopard has the same welcome video as Leopard), with the only difference being that it now plays in a window, not full-screen.

Changes and new features

Although Mac OS X 10.6 features literally hundreds of tweaks, those mentioned below are some of the more noticeable ones:

General:

Snow Leopard is noticeably more responsive than Leopard on the same hardware, and after installing it you’ll regain several gigabytes of disk space.

In Leopard, if the user tried to eject a disk that was in use by an application, they would see a message informing them that the disk is in use, but without any further details. In Snow Leopard, this notification now tells the user which application is using the drive they’re trying to eject.

Unfortunately, the old Aqua-style glowing blue buttons haven’t been replaced with the new Marble-style buttons system-wide yet.

Keyboard Shortcuts and the Services menu have been neatened up and are manageable through System Preferences (on the Keyboard Shortcuts tab of the Keyboard pane). Services are now context-sensitive and will attempt to only display Service options relevant to what the user is doing at the moment.

OS X 10.6 features automatic text substitution using the same word list across all applications that support it (for example, “teh” will automatically be replaced with “the”), and the list of terms and their substitutions can be viewed and modified on the Text tab of the Language & Text pane in System Preferences.

Screenshots now have more descriptive names than the “Picture 1″, “Picture 2″, etc. they had in Leopard – Each screenshot is named after the date and time that it was taken on.

If you travel a lot, Snow Leopard’s new Core Location technology can detect your location and automatically update your time zone based on nearby Wi-Fi hotspots it detects (similar to how the iPhone can find your location on a map without the use of GPS).

64-bit:

While Leopard supported 64-bit applications in many ways, Snow Leopard went a step further in that all system applications were rewritten in 64-bit code, allowing them to be faster and more secure.

Grand Central Dispatch:

Grand Central Dispatch is a new feature in Snow Leopard that makes OS X multi-core aware and optimizes it for allocation of tasks across multiple cores and processors.

OpenCL:

OpenCL in Snow Leopard makes it possible for developers to tap into the processing power of the Mac’s graphics cards and use them as additional processors for everyday applications.

Microsoft Exchange:

The iPhone’s had Microsoft Exchange support since 2008, and OS X now has the same email, contact, and calendaring features built-in by default (something which, ironically, Microsoft Windows doesn’t).

Whereas Leopard users had to set up Exchange connections as IMAP accounts through Outlook Web Access, Snow Leopard offers the ability to set up connections to Exchange servers in two simple steps for Mail, iCal, Address Book, or a combination of the three.

Malware Protection:

Leopard offers some malware protection in that it warns users when they mount disk images or run applications downloaded from the Internet for the first time.

Snow Leopard has additional protection built-in that will check applications and installer packages against a list of known dangers. Funnily enough (and as a testament to the Mac’s security), this list currently includes only two entries. It is, however, easily updateable by Apple via Software Update.

Exposé:

In Leopard (and previous versions of OS X), Exposé would zoom out and semi-randomly arrange all open windows on your screen with their titles displayed when the mouse moved over them.

In Snow Leopard, the windows (including minimized windows, which are displayed below a horizontal line) are arranged in a grid with the titles of the windows always displayed below them.

There are two new keyboard shortcuts available in Exposé for Snow Leopard:

• ⌘-1 (Command-1:): Arrange windows alphabetically
• ⌘-2 (Command-2:): Arrange windows by application

Exposé in Snow Leopard has also been integrated into the Dock. Clicking and holding on any application icon will cause Exposé to display all of that application’s windows.

The Dock:

In Snow Leopard, the Dock’s right-click menus are now a shade of transparent black with a light gray border, and Stacks displayed in a grid feature a scrollbar to the right side of the Stack.

In Leopard, minimized windows become small icons on the Dock to the right of the vertical divider with one icon for each window.

In Snow Leopard, turning on the “Minimize windows into application icon” option in the Dock panel of System Preferences will cause windows to be minimized into their application’s icons on the Dock.

Minimized windows can be restored by selecting them from the application’s Window menu, by right-clicking on the application’s icon in the Dock and selecting the window, or by clicking and holding on the application’s icon in the Dock to see all of its windows in Exposé, then clicking on the window.

The Finder:

In Snow Leopard, the Finder has been completely rewritten as a Cocoa-based application which makes it more responsive, gives it better support for 64-bit mode, and allows threading using the new Grand Central Dispatch technology built into OS X for multicore machines.

Additionally, icons can now be as large as 512×512 pixels, and in Icon View the icon size can be controlled by a slider in the bottom right corner of the Finder window.

These larger icons also allow you to page through certain types of media (e.g. iWork, Office, PDF documents) by hovering the mouse over them and clicking on a left / right arrow icon.

Media files (e.g. QuickTime movies and MP3 clips) can be played in their icon by hovering the mouse over them and clicking on a Play button. Moving from icon-based playback into Quick Look- and then Fullscreen-based playback is seamless and doesn’t require that you restart the movie.

Preview:

In Snow Leopard, Preview now accurately detects columns in PDF documents and let you select text on a column-by-column basis instead of highlighting across the entire width of the page.

The new version of Preview can also detect images on cameras connected to your Mac as well as import, view, and adjust images from connected scanners.

Additionally, Preview features a new “Contact Sheet” view that will show thumbnails of all open documents (similar to how “Thumbnail View” shows thumbnails of the current document’s pages).

Quicktime:

The latest version of QuickTime included with Snow Leopard (QuickTime X) features a complete visual redesign that does away with any extraneous window elements.

When the mouse is not hovering over a movie, the entire QuickTime window displays the movie content. Moving the mouse over the movie will fade in its titlebar and controls.

Related posts:

1. Review: Zooom/2 for Mac OS X Leopard and Snow Leopard
2. Forcing the Dock to be displayed in 2D on Mac OS X
3. Making hidden application icons transparent on Mac OS X
4. Displaying gradients behind Stack items on Mac OS X
5. MySQL 5, PHP 5 and Apache2 configuration on OS X 10.5.* (Leopard)