But what about the other major function of a laptop-viewing and editing Microsoft Office documents? Well, it turns out you can do that, too, on these devices, at least to a point. Currently, you can read Word, Excel and PowerPoint files, as well as Adobe PDF files, on certain handhelds; you can even edit them and synchronize the changes back to a PC.

Here’s a look at how that’s possible, on the three most popular types of smart phones and PDAs in the U.S.: those powered by the Palm operating system, those powered by the Windows Mobile operating system (formerly known as Pocket PC), and the BlackBerry, which uses both hardware and software from RIM.

First, make sure your device has lots of storage capacity, either in internal memory or on a removable memory card, if your device can accept them. (The Treo, the iPAQ and most other devices running Windows Mobile software can; BlackBerry models cannot.) You will need that room to store your Office documents.

Second, I strongly advise those wanting to edit documents to buy a phone or PDA with a full keyboard, rather than one that relies solely on handwriting recognition or a phone keypad. The software for viewing and editing documents does work on devices without a keyboard, but unless you just want to read documents, the process is painful on these models.

You might think that the devices running Windows Mobile software would do the best job of handling Microsoft Office documents because both systems are made by Microsoft. Or you might imagine the BlackBerry was tops at this task because it is bought mostly by corporate computer departments, where Microsoft Office is the application software of choice. But in fact, the best devices for viewing and editing Office documents are those using the Palm operating system, such as the Palm Treo 650. That’s because of a helpful third-party program, Documents to Go, from DataViz, which is packaged with many Palm devices, including the Treo.

Next best are the Microsoft-powered phones and hand-helds, which come with built-in mobile versions of Word, Excel and PowerPoint. Bringing up the rear is the BlackBerry, which can display Word, Excel and PowerPoint files when sent as e-mail attachments, but doesn’t let you edit or synchronize them with a PC.

Palm OS devices. The best smart phone on the market is the Treo 650, produced by Palm and powered by the Palm operating system, which is made by a separate company called PalmSource. While the Palm software lacks the built-in capability to read or edit Office documents, the Treo comes bundled with Documents to Go, which can import and open Microsoft files in their native formats without downsizing them to some special “pocket” version. It also allows you to edit, or even create, these types of documents and synchronize your changes with versions on your PC.

You can get the documents into your Treo or other Palm device either by receiving them as e-mail attachments or via synchronization with your PC. Documents to Go includes a computer program that performs this document synchronization; I use it often on my Treo 650. It displays documents in their actual fonts, including colors and attributes like underlining, bold and italics. Indents and spacing are also preserved. The Treo 650 doesn’t support different font sizes, and it doesn’t include a spell checker. Documents can be opened from, or stored to, either the device’s internal memory or a memory card. You can also zoom the screen to show more or less of the document, especially important with spreadsheets, which often sprawl across the page and can be hard to read when resized to fit entirely on the small screen. PowerPoint files can be edited and synchronized only if you are using a Windows PC, though they can be viewed if you are using a Macintosh.

In my tests over the years, Documents to Go performed flawlessly, better than the built-in mobile Office programs on Windows-powered handhelds. In addition to being bundled with the Treo and some other Palm devices, Documents to Go is available for independent purchase, in several versions, for $30 to $90, depending on features. There are also versions for smart phones that use the Symbian operating system, including models from Nokia and Sony Ericsson. You can find information and purchase Documents to Go at www.dataviz.com [http://www.dataviz.com].

Windows Mobile devices. There are two kinds of devices powered by Microsoft’s Windows Mobile software. Some are confusingly named “smart phones,” though they generally lack keyboards and some key software capabilities, including the ability to edit Office documents. Others are full-featured handhelds, including some with keyboards, such as several of HP’s iPAQ models, the new Samsung i730 phone and the very latest and greatest Windows Mobile device, the Treo 700w.

The new Treo is the first device built by Palm to eschew the Palm operating system for Windows software. While it’s mainly aimed at the corporate market and, in my view, isn’t as good as the Treo 650, the 700w is probably the best Windows Mobile device. On the new Treo and others, you can read, edit and create Word and Excel files, and synchronize them with your PC. You can view PowerPoint files, but not edit or create them.

As with the Treo 650, you can get these documents into your device either by receiving them as email attachments or by copying them from a PC.

While the mobile Office programs on the Windows devices work okay, they aren’t quite as good as Documents to Go, in my experience. For instance, in a recent test I opened a simple Word document on two Treosa 650 running the Palm OS and Documents to Go, and a 700w running Windows Mobile and its built-in Office Mobile programs. Documents to Go opened the program perfectly in its Times New Roman font and sized it so the words were distinct, and the formatting was preserved. The Word Mobile program in Windows Mobile displayed the document in a different font and in a size that screwed up the formatting. And while Documents to Go allows you to create and edit PowerPoint files, Windows Mobile doesn’t.

BlackBerry. The BlackBerry can view Office documents when received as e-mail attachments, but the function is pretty primitive. You can’t directly import documents or synchronize them with a computer. And you can’t create or edit them, even though you have a full keyboard at your disposal.

There is a third-party program for the BlackBerry that claims to allow editing, creating and synchronizing of Word and Excel documents, but not PowerPoint files. It’s called eOffice, made by a company called DynoPlex, and it’s available in versions ranging from $120 to $200 at www.dynoplex.com [http://www.dynoplex.com].

I wouldn’t want to write a long report on a Treo. But in a pinch, I could have written this column on one. And editing a document like this is a breeze. So you really can leave that laptop at home, at least some of the time.

The daunting security problems that have plagued Windows have also prompted many of its users to take a serious look at the Mac. This trend has been further reinforced by the “iPod halo effect,” in which Windows users who own and love Apple’s iPod music players are willing to consider the company’s other products. As a result, Mac sales, while still relatively small, have been growing much faster than overall personal computer sales.

Are you among the PC majority considering a switch to the Mac? Then you probably have some important questions.

How do Macs compare in quality with Windows PCs?

I believe that, at the moment, Apple makes the best computers, and the best operating system, for mainstream consumers doing typical tasks — e-mail, Web surfing, office — productivity functions such as word processing and presentations, photo organizing and editing, playing and collecting music, and editing home video.

Of all the major computer makers, Apple is the most focused on consumers and small businesses. Most make the bulk of their money, and take most of their cues, from the information-technology departments of large corporations.

Apple’s iMac G5 consumer desktop is, in my opinion, the single best home computer on the market. Its PowerBook laptops are among the top portables.

Do Macs run Windows and Windows software?

No: Out of the box, Macintosh computers run only Apple’s own operating system, called OS X, and software written by Apple and other companies that is designed to run on OS X.

You can rig a Mac to run Windows and Windows programs by installing a special, $250 Microsoft program called Virtual PC, which creates a virtual Windows computer inside the Mac. But I don’t recommend this for frequent use, because the faux Windows computer it creates is relatively slow and is susceptible to the same viruses and spyware as a real Windows machine.

How does Mac software compare with Windows?

The Mac’s OS X operating system, the latest version of which is called Tiger, is far better than Microsoft’s aging Windows XP and already boasts many of the key features Microsoft plans to include in its 2006 version of Windows, called Vista. And the Mac comes with an excellent suite of free software that’s generally superior to comparable Windows programs that cost extra.

Out of the box, the Mac has better photo, music, video and DVD — creation software than any Windows computer I’ve seen. It has a better free email program and Web browser than Windows does, a better free word processor and much better search capabilities.

About the only software a typical consumer would have to buy for a new Mac is the Mac edition of Microsoft Office. It includes versions of Word, Excel and PowerPoint that are very similar to their Windows counterparts, and a program called Entourage that is different from Microsoft Outlook but performs the same functions.

Are Macs more secure than Windows PCs?

Yes. Since the OS X operating system came out in 2001, there has never been a report of a successful virus for it — that is, a virus that has infected numerous computers, and spread from computer to computer, outside of a lab. And there is little or no known spyware for the Mac. By contrast, there are tens of thousands of viruses for Windows and untold numbers of spyware programs. Just as regular Windows programs can’t run natively on a Mac, none of these malicious Windows-specific programs can run on a Mac either.

The Mac isn’t invulnerable, but it has better built-in security than Windows, and such a small market share that virus and spyware writers haven’t targeted it yet. As a result, most Mac users have been able to dispense with running the morass of security software that Windows users must employ.

Are Mac files compatible with Windows files?

Yes. Unlike older models, the current Macs have been specifically designed for compatibility with Windows PCs. The Mac OS and software can handle, without translation or conversion, all of the common types of files you use on a Windows PC. You can copy to a Mac all your pictures, MP3 music files, text files and Adobe PDF files, and they will open right up in Mac programs. There are also free Mac versions of the Real Player and Windows Media Player, and of Adobe Reader.

Microsoft Word files also can be opened, edited and created in Apple’s free, built-in text editor. And if you buy Microsoft Office for the Mac, all Office files, including Word files, Excel files and PowerPoint files, can be opened, edited and created on the Mac. Office files created on the Mac can be opened and edited in Windows Office, and vice versa.

Some specialized files created by particular programs, like database files or financial files, won’t be usable. For instance, the Mac version of Quicken is quite different from the Windows version and uses a different file format.

For occasional use of these programs, you can install Virtual PC.

In addition, nearly all keyboards, mice, monitors and printers made for Windows computers can be used with a Mac, if they connect via the industry-standard USB or FireWire ports. Macs can also share networks with Windows PCs and even look into the hard disks of Windows computers, and vice versa.

Is there anyone who shouldn’t consider a Mac?

Yes. Serious game players should stick with Windows PCs, which are much better game platforms and can run many more game titles. People who use specialized software or custom corporate software for which there isn’t a Mac equivalent should stick with Windows. While the Mac has rich offerings in mainstream software categories, it has only a fraction of the niche software and specialized business software that Windows does.

Also, you should stick with Windows if your home computer choices are dictated by your company’s IT department and the IT department is ignorant of or hostile to the Mac, as so many are. Although modern Macs are designed to access corporate Windows networks, and many do, if your IT department won’t help you with the transition, it’s not worth the headache to switch to the Mac.

Ten years ago, when Apple was stagnant and its products troubled, I recommended that consumers shun the Mac. If Apple’s quality and innovation slip, I might revert to that position. But for now, the Mac is the best computer, with the best operating system and the fewest security problems, for average consumers.