With each new release, including the OS X 10.4 Tiger release, Apple continues to build on its successful OS X operating system. For most users, the Unix underpinnings remain an unseen foundation, but for those willing to venture past the graphical user interface, the Unix base provides power and capabilities not available in many commercial desktop OSes.

The four new features that are likely to be used most often, and produce the most significant changes in work habits, are: Spotlight, a new search service embedded within the OS; its cousin Smart Folders, which can dynamically contain the ongoing results of any Spotlight search; Automator, which allows you to automate repetitive tasks; and Dashboard, an environment for running Widgets (accessory applications).

Installing a Mac OS is traditionally an easy task, one that puts the cumbersome install processes of other OSes to shame. Tiger maintains this tradition, with one potential stumbling block for some individuals. Tiger is only distributed on DVD. If your Mac has only a CD drive, you must contact Apple directly for a CD version.

Otherwise, installing Tiger is a simple, fast, and straightforward process. The install process includes the option to copy personal data from other computers or partitions and skip the time-consuming task of manually moving data and applications from one computer to another.

For existing OS X users, the most obvious changes in the desktop's appearance are the addition of a magnifying glass icon on the far right of the desktop menu bar, and the addition of the Dashboard icon to the Dock.

Using Spotlight is as easy as clicking the magnifying glass icon and entering a search phrase. When Spotlight displays matches it organizes them by category, such as Documents, Email Messages, and PDFs.

Spotlight is not only able to look into file and folder names, it can also look into the data of most applications, including Mail, Address Book, iCal, Microsoft Word, Adobe Photoshop, and Adobe Acrobat (PDFs), to find matches for your search terms. You can also configure Spotlight to ignore certain locations, such as specific folders or whole hard drives, which is handy if you have networked drives mounted.

You can save Spotlight searches as Smart Folders. These folders maintain your search terms and are constantly updated. Open a Smart Folder, and you will find all current matches to your search within it. Smart Folders may prove to be a great new way to organize your work. You can have a Smart Folder that contains all of the Word documents you worked on in the past week, or a Smart Folder that lists all of your photos by category. Add new photos to your Mac, and the Smart Folder will automatically update.

Automator is a new application that allows you to visually build repetitive workflow processes, quickly and easily. You could automate a task such as checking mail, looking for mail from a specific individual or group, checking that mail for attached photos, moving any attached photos to iPhoto, automatically categorizing them, and then sending a thank you message in response to the sender.

Automator workflows are easy to build; no programming skills or special jargon required. Simply launch Automator, which will display a library of Automator actions taken from all of the applications that are currently installed on your system. Drag each target action to the workflow pane, and Automator will chain them together.

Dashboard is a special desktop environment used to run Widgets. Widgets are mini-applications usually designed to perform one simple task, such as get a stock update or check the weather. Clicking the Dashboard icon in the Dock brings up the Dashboard environment, with any Widgets you have previously selected.

Apple prepopulates Dashboard with Widgets, such as Calendar, Address Book, and Weather. There are currently more than 600 Widgets available for downloading from the Apple web site, so you can have your own custom collection of Widgets at your fingertips. Currently available Widgets include BusinessWeek Desktop Headlines, Package Tracker, Amazon Search, eBay Search, and Hotel Finder. There's even a Widget for finding the closest Pizza Hut.

In addition to new features, Tiger also includes updates. Safari, Apple's web browser, is now at version 2.0. It includes new support for RSS feeds and faster rendering times. QuickTime 7 includes support for H.264 video codec, which delivers remarkable video quality at very low data rates, making it ideal for streaming video and for next-generation video storage formats. H.264 was selected for use in MPEG-4, HD-DVD, and Blu-ray DVD players. iChat 3 includes videoconferencing for up to four locations, and audio conferencing with up to ten people.

For developers, Tiger includes Xcode 2, Apple's preferred development environment. Xcode 2 provides all of the tools you need to develop the next big thing (except your imagination), whether it's a new Cocoa application or a humble AppleScript. Fully integrated Xcode developer tools include editors, debuggers, and the Interface Builder, one of the easiest ways to build an application's graphical user interface.

Apple OS X 10.4 boasts more than 200 new features. Many of the new features are only noteworthy to software developers, but taken together, the changes provide a very stable and useful OS.

Pros: Smooth, stable OS update, more than 200 new features and upgrades
Cons: Distributed on DVD, only available on CD by contacting Apple directly for a media exchange