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NN/g Home > AskTog > Columns > Trends: Evolution of the Inteface Originally published in MacWorld, September, 2000

Trends: The Evolution of the Interface

By Bruce Tognazzini

Mac users are in for a big change. OS X her-alds a new era in the Macintosh user experience -- an era where the Mac is more powerful and reliable than ever before. At the same time, the operating system's flashy new Aqua interface, along with the increasing number of tools that let you change the very underpinnings of the OS, may threaten the Mac's hallmark simplicity.

The Way We Were  No Mac user would feel any confusion seated in front of a 1984 Macintosh running System 1.0, but most would be surprised at just how primitive the operating system was. Apple hadn't yet even thought of much of what we take for granted on today's Macintosh. In those early days, you could open only one application -- including the Finder -- at a time.

Even as memory increased, tight integration of applications with each other and with the Finder remained elusive. Our sole tool was the Switcher. This illusion, developed by Andy Hertzfeld, switched between applications by sliding the current one off to the left as the new one slid onto the screen from the right. You could get to any open application by sliding, but only one application at a time appeared on screen.

Then, one fateful day in 1985, shortly after I founded the Apple Human Interface Group, a couple of UC Berkeley kids took the bus down to Apple to show the core Mac team a Mac Plus running MacWrite. We were not impressed. We'd seen MacWrite before. But when they shrank the MacWrite window that filled the screen, suddenly we could see the Finder running beneath. Apple's best and brightest gawked, gasped, and then broke into excited chatter. We'd never thought of such a grand illusion. When the two students returned to Berkeley late that afternoon, it was in the back of a stretch limo, and today's MultiFinder was born.

The Way We Are  Since that leap, many new objects and behaviors have slowly built up on the Mac -- from hierarchical, pop-up, and tab menus to drag and drop -- giving us what has been, until now, the simplest, most powerful human-computer interaction system ever made. But now progress more often responds to Microsoft, rather than the other way around. Even today, the company lags in such critical areas as uninstalling applications and memory management.

Mac OS X could accelerate the Mac well beyond the reach of its competition once more. It corrects the single biggest interface problem Mac users have faced from day one: lack of reliability. Apple has, over the years, given users tools to deal with crashing applications (such as pressing command-option-esc). However, the proper cure is to eliminate the problem in the first place. That's what OS X does. But under OS X, will this reliable computer still really be a Mac?

What Makes a Mac a Mac?

With the Mac, you have always had the power to move around and organize applications and documents in your own virtual space, maintaining a neat or cluttered workspace, as is your habit. Other desktop systems, from Windows to Unix, have depended more on abstraction, forcing users to remember the location of objects in complex hierarchies. In theory, all of this reduced clutter, but it really only moved the clutter from the visible desktop to the back of your mind. Since most of us work better with visible clutter than with rote memorization, our efficiency drops.

Taking Away Control  Early releases of OS X threatened to follow the same path, with the Trash Can and all other standard desktop objects thrown into the Dock, where they randomly bounced about as new windows and applications opened. In the last six months, much has turned around, with beta versions of the new OS becoming progressively more Mac-like.

OS X is still missing some important objects, most notably OS 9's tab menus -- capable of holding hundreds of clearly labeled items -- at the bottom of the screen. The Dock, containing perhaps 20 or 30 icons, has replaced these. It is beautiful to behold, but a drop in bottom-edge storage by several hundred items represents a significant backward step.

In 1985, after a year of finding that pretty but unlabeled icons confused customers, the Apple human interface group took on the motto "A word is worth a thousand pictures." This still holds true. Unfortunately, the labels for Dock icons don't appear until the mouse passes over them. A user looking for one of six Word documents must scrub the mouse back and forth along the length of the Dock until a particular label appears.

Introducing Abstraction  The Mac has held the advantage for years with its spatially oriented file system. OS X's new File Browser instead brings the power of Web browsers to the local desktop. Unfortunately, the Web and your desktop are not the same thing. On the Web, you typically search through millions of Web sites with billions of pages for something you didn't make yourself. A search through your personal machine is quite different -- usually you're looking through a smaller number of files created by or collected and organized by you.

Perhaps the File Browser will find its niche in local area networks, where users may need to traverse large numbers of documents they haven't personally created or collected. However, if I know Mac users, they want to organize their lives in their own ways.

The Perils of Customization

OS X's interface isn't the only issue at hand. So, too, is its profound gift for customization. Customization can give us the power to make our computers look and act the way we want. But we need look no further than Windows to see how it can be misused.

Skin Deep  For several years now, Macintosh users have had the ability to customize their Macs, but only at a superficial level. For example, Skins are special files that can change the Finder or an application's color scheme and general appearance. Some skins are beautiful, some are hideous, but the most damage they can do is to aesthetics. A few other programs, such as QuicKeys and AppleScript, let us go further to automate particular sequences of events, but we still can't radically change what applications or the OS can do.

OS X provides the hooks that allow third-party developers to affect the user experience profoundly. In the future, you will have direct access all the way down to the Unix Console window (a scary sight indeed) -- and you will discover scores of freeware and shareware widgets that change the very underpinnings of the OS and applications. Instead of getting a new skin that makes your system look like the latest and greatest Linux interface, for example, you'll probably actually get the latest and greatest Linux interface.

The first addenda to the interface to appear will likely erase any perceived strayings from the path of the True Mac in the new OS X interface. This task behind them, the Mac community will start "improving" the interface. Some improvements will be cute but inconsequential. Some will seriously erode the user experience. Others will be as wonderful and astonishing as MultiFinder. With luck, Apple will once again employ a few late-afternoon limos, gathering the coolest ideas into the fold.

Keeping It Simple  Some wonder if the age of simplicity has passed Apple by. How can an OS as powerful as X possibly regain the sleek elegance of the Apple of old (no matter how flashy the demos)? The simple truth is that an interface is only as sleek as its OS is powerful. The Palm Pilot works because the interface with its relatively limited universe of functionality sits on a computer with significantly more power and storage than even the original Mac. OS X has the horsepower to command and control a far larger universe of activities than we have ever seen on personal computers.

Does Apple still have the talent and the drive to achieve that ultimate simplicity? Will it go down the garden path trod by Microsoft, Sun, and others, building tractors for the masses? Or will OS X live up to its demos and mature into a slippery new sports car? Whether we end up with a Caterpillar or a Porsche, the next year should be an exciting ride.

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