If the pen were mightier than the keyboard, the typewriter would have died in its infancy, and we'd all be scribbling on our computers today.

But truth be told, writing by hand is a slow, uncomfortable process for most of us (schoolteachers excepted). It's non-standardized, making handwritten communication haphazard at best. There's always a good chance you won't be able to read my handwriting. In fact, there's a good chance that I won't be able to read my handwriting.

So, having developed a perfectly good interface for today's PCs - the keyboard and mouse - computer makers have struggled for years to build PCs that you can write on with a pen. Remember the Go PC? Or Windows for Pen Computing? Or the Apple Newton? None worked well enough to be useful.

But this year's crop of new "tablet" PCs brings pen-based computing much closer to reality. These machines (including the Compaq TC1000 I reviewed last week) work much better than their predecessors do thanks to faster processors and a pet project of Microsoft Chairman Bill Gates known as Windows XP Tablet PC Edition.

This superset of Windows XP Professional is designed to turn a stylus into a usable input device, and with some caveats, it succeeds.

There are indeed situations where it's neither convenient nor polite nor even possible to tap on a keyboard. If you frequently take meeting notes on a legal pad and then transcribe them, or you're in a profession where you're on the go and spend time filling out forms (health care, real estate, sales, etc.), Windows Tablet Edition could make life easier.

Tablet Edition looks a lot like regular XP, with additions. First, it allows a stylus to replace the mouse and keyboard. The mouse part - tapping the screen and dragging - takes some getting used to, but if you've used a laptop with a pressure-sensitive track pad, you'll figure it out quickly.

The stylus interface has two annoying omissions for experienced Windows users. There's no substitute for the keyboard's Alt-Tab function, which cycles between open applications, or for the Windows-M keyboard shortcut that minimizes all open panes. That means too much poking, closing, moving and dragging when several programs are running.

To replace the keyboard, Windows Tablet Edition offers two choices of stylus-based input, plus voice recognition.

A new applet called Input Pad translates pen strokes into actual text and inserts it into applications such as Word, Excel or Outlook.

Input Pad displays a writing area with one or two lines on which you can write cursively or print in your normal hand. There's no need to master the modified alphabets that handheld computers require. When you reach the end of a line, you can hit a "Send" button or pause for a second. Windows processes your handwriting and inserts text in the document. With a two-line pane you can write at almost normal speed.

In addition, a "write anywhere" feature pops up a handwriting entry line within a program, so it appears that you're actually writing in a Word document, but I preferred the Writing Pad.

Input Pad can also simulate an on-screen keyboard, which is accurate but agonizing for anything longer than an e-mail address.

My results were mixed. When I wrote normally, with some care, recognition was reasonably accurate. But strange words, proper nouns and slips of the pen produced hilarious results. For example, I had to try 17 times before Windows would translate "Himowitz" correctly.

I ascribed this to my dismal scribbling, so I asked for newsroom volunteers with "schoolteacher" handwriting. Journalists are not noted for penmanship, but 10 brave souls agreed to try. Some had better results than I, others worse, but all were surprised at how well the handwriting recognition worked.

My accuracy improved when I "undocked" the Input Pad and shifted it from the bottom to the middle of the screen, which provided better hand support. I also learned that switching from the writing pad to the on-screen keyboard made using e-mail addresses and hard-to-translate words and phrases faster and easier.

Is this scheme a substitute for a real keyboard? Certainly not on a long-term basis. Even Microsoft doesn't trumpet Windows Tablet Edition for handwriting recognition. Instead, its centerpiece is an entirely new note-taking applet called Windows Journal. It employs a new and clever data format called Ink to store and retrieve pen strokes.

When you create a note in Journal to begin writing, it looks like a blank sheet of ruled notepaper (other backgrounds are available). You can write on a page just as you would on a real notepad, in a variety of pen widths and colors. You can write text, doodle around, or draw diagrams. An eraser tool rubs out mistakes.

But unlike a regular notepad, this one doesn't run out of pages, and you can insert space between existing items if you've forgotten something. Try that with paper.

Using an intuitive lasso tool, you can circle words or paragraphs and apply handwriting recognition. Unfortunately, this isn't as successful as the Input Pad's real-time interpretation, because it doesn't provide clues from your pen movements. But an input box allows you to correct errors. The text can then be added to your note in standard format or transferred to another program.

Journal also invites users to drag photos and other graphics into a note, or insert any standard Windows document, such as a report created in Word. Journal creates an internal image of the document, which you can highlight or annotate by hand.

All of this worked elegantly and transparently on my test tablet PC - a sign of top-notch programming. Journal would be a natural for college students taking notes in class. The question, though, is how many people really want to pass information around this way. It's convenient to send handwritten material electronically, but only if your penmanship is good enough for others to understand in the first place.

Notes can be exchanged in their original format with other Tablet PC users (a rather limited audience), or viewed by anyone with Windows 2000 or XP who downloads free software from Microsoft's Web site.

To reach the 90 percent of the world's PC users with earlier Windows releases, Journal users have a choice of sending a note as a monochrome TIFF image (a bad idea) or as a compressed Web page archive viewable with Internet Explorer 5 or later (a more workable approach).

Microsoft has created a set of free downloadable extensions to Office XP that allow tablet PC owners to insert Ink markup into Word, Excel, PowerPoint and Outlook documents. Several third-party tablet programs are also available, including graphics programs from Corel and Alias/Wavefront. Links to demo versions are available on Microsoft's Tablet PC page (www.microsoft.com/windowsxp/tabletpc/).

The bottom line: Microsoft's Tablet software works, if you're willing to put up with its quirks. As a newspaperman, I can see a definite value in Journal for note-taking outside the office. It you'd benefit from a tablet PC, the technology is worth trying.

However, there is a question of prudence. For daily work and personal use, electronic notes are a great idea. But in business, government and labor negotiations, handwritten paper notes are legally admissible evidence. So are a reporter's notes. It's difficult to alter them without detection, and outside of fire, flood or theft they won't disappear.

Like all digital records, handwritten notes stored electronically can be altered. Hard drives can crash, taking notes with them. No one has tested the legal implications of switching to an electronic medium. Pen-based computing may have arrived from a technical standpoint, but I'd be careful about when and where I use it.