Whether you've just unpacked a shiny new Mac or you're hoping to get an older machine into shape, your first step should be to perform some initial cleanup and preparation tasks. These steps will help your Mac run better right now, and will make ongoing maintenance tasks easier.

Install the Latest Version of Mac OS X

If your Mac is already running the latest and greatest version of Mac OS X, good for you! Skip to the next section. If not, your first step should be to upgrade.
Every release of Mac OS X includes dozens if not hundreds of bug fixes that prevent crashes or other errors and that patch holes that ne'er-do-wells might use to damage or gain access to your system. That fact alone is reason enough to keep up to date. In addition, Apple constantly introduces useful new features, and some newer software runs only on recent versions of the operating system. Often, doing nothing more than updating your system software can eliminate a wide range of problemsand prevent others.

Mac OS X updates fall into two categories: major and minor. Major updates (more properly known as upgrades) increment the digit after the first decimal point in the version number: 10.2, 10.3, and 10.4 were all major updates. With rare exceptions, Apple charges money (typically $129) for major updates. Minor updates increment the digit after the second decimal point: 10.4.2, 10.4.3, and 10.4.4 were all minor updates. Minor updates are always free.
Without exception, you should download and install every minor update. (I do, however, suggest waiting a few days after an update appears to make sure it doesn't contain any serious errors.) The easiest way to do so is to use Software Update (see the next section). Major upgrades are less urgent, because they focus primarily on new features. But because they also fix numerous bugs, you should consider buying and installing them.

Some Mac users, having heard horror stories of half-baked releases that cause as many problems as they fix, feel anxious every time a software update appears. I won't lie to you: major errors occasionally sneak into system updates. But this happens rarely, and in most cases Apple resolves such problems promptly. In addition, a fair number of errors that appear to be update-related are in fact the result of existing problems on the user's machine, minor issues such as incorrect permissions, or even (gasp!) user errors. I can't guarantee that a software update will never break anything, but in my experience the benefits of incremental updates overwhelmingly outweigh the risksespecially if you maintain good backups.

Turn On Software Update

Mac OS X includes a feature called Software Update, which checks Apple's servers periodically to see if free updates exist for any Apple software on your computer, and, if so, offers to download and install them for you. Software Update is the easiest way to keep your Mac up to date with bug fixes and minor enhancements, and I strongly recommend that you use it.

Note

I want to reiterate that Software Update handles only Apple software (including Mac OS X as well as applications such as iLife, iWork, Logic, and Aperture).

Software Update is enabled by default, but you should check to see that it's still on and that its options are configured optimally. To set up Software Update, follow these steps:

At the interval you set, Software Update checks for new software. When it finds some, it displays a dialog in which you can select any or all of the updates for immediate installation, defer them to a later time, or remove items from the list entirely.

Software Update vs. Manual Updates

In general, software packages that Apple makes available through Software Update are also available on the company's Web site, so you can download them manually if you wish from www.apple.com/support/downloads/.
Starting with the second minor release of each Mac OS X versionsuch as 10.4.2 for TigerApple typically produces three separate updaters: the updater available only through Software Update, known as a "patch" or "smaller-sized delta" updater; the standard (or "regular-sized delta") updater; and the "combo" updater.
Delta updaters require the most recent previous release to be installed; for example, a 10.4.6 updater would require that 10.4.5 already be installed. A combo updater, on the other hand, will update any previous version of the major system release (in this example, any release from 10.4.0 through 10.4.5) to the new version. Because of this, combo updaters are always largerin some cases much larger. Software Update chooses the smallest applicable updater, which means it chooses the smaller-sized delta updater if you run Software Update regularly.
Why should you care? Well, on a few occasions, users have found that using the delta updaters (whether manually or via Software Update) for some reason left out essential files that prevented proper operation of some Mac OS X features, whereas these files were included when the same users applied the combo updater.
Although I've never had problems with the delta updaters, anecdotal evidence suggests that you may have a slightly lower risk of problems if you manually download the combo updater for each Mac OS X update instead of using Software Update.

Update Third-Party Software

Software bugs are a fact of life, but in general, applications improve with each release. You can avoid, or solve, many maintenance problems simply by making sure you have the latest version of every program installed.
Note
In some cases, getting the latest version of a program means spending hundreds of dollars on a major upgrade. In cases where you can't afford the absolutely latest version, you should at least install the latest free update you can find. This may require some searching on the company's Web site; earlier updates may not be featured as prominently as the most recent update.

Because Software Update handles only Apple software, any other developer wanting to offer similar capabilities must devise a separate update mechanism. Happily, almost every major application (and a good percentage of minor ones) contains some sort of software update feature. Unhappily, they don't all work the same way. Some of them check for updates on a schedule, while others don'tand of those that do, not all have this feature turned on initially. Some programs can download and install new versions of themselves automatically, while others simply download a disk image and expect you to open it and run the installer yourself; still others do nothing but open a Web page with links to updates you can download manually.
In an ideal world, updates would require no intervention other than a single click to confirm that you're aware of, and approve of, the installation; everything else would happen automagically. Because only a few applications currently offer that level of automation, though, you may have to perform some extra steps.
I describe how to handle ongoing updates ahead. For now, do just two things:

• Make sure all your software is currently up to date. In each of the applications you use frequently, look for a Check for Updates command (the wording may vary). Such commands usually appear in the application menu (the one bearing the application's name), the Help menu, or the Preferences dialog. If you can't find such a command, visit the developer's Web site.

Don't forget: Be sure to check for updates of preference panes, menu extras, plug-ins, Dashboard widgets, and other system enhancements. These types of software frequently lack an automatic update feature.

• Turn on any automatic software update features your applications may have. Again, check each application's Preferences dialog for a checkbox that enables scheduled updates, and if you can choose how often to check, choose the most frequent option.

Grip

Some applications check for updates every time you launch them, and display an intrusive alert after each check just to tell you that no updates are available. Ugh! An alert of that sort should appear only after a manual check for updates. In such cases, I either turn off automatic checking or change it to a weekly or monthly check.