In trying to reach that goal, Apple has built OS X around Unix, a stable but imposing operating system that is popular in servers and high-end workstations. To make Unix more friendly, Apple has added its own graphics technologies and user interface, a combination that the company touts as the best of both computing worlds.
"Other companies have been trying to tame Unix for the mere mortals out there," said Avie Tevanian, Apple's senior vice president of software engineering. "Everybody to date has failed."
OS X is the first complete rewrite of the operating system since the Mac was introduced 17 years ago. By using Unix, OS X has features that give it the stability and robustness the company hoped to add when it first tried to develop a new OS in 1994.
One of two key features is protected memory, which means that if one program crashes, the rest of the system keeps working. The other is pre-emptive multitasking, which allows a person to keep working at full speed while the computer performs other calculations in the background.
Analysts say the first implementation of OS X, which goes on sale Saturday, has its flaws but that Apple appears to be headed in the right direction.
"The Unix core has the stability that I think users are looking for," said Tim Deal of Technology Business Research. "It's kind of the first step in an ongoing process."
However, to take advantage of all of these features--and the new user interface--third-party applications must be modified for OS X. They don't have to be rewritten from scratch: Apple estimates that 95 percent of existing code written for previous Mac operating systems works just fine in OS X. But the process of finding the 5 percent of bad code and adding lines of new code can be time-consuming.
Macromedia, for example, said it has been working for a year to make its FreeHand graphics program ready for OS X.
Many of the thousands of programs being modified for OS X, such as Microsoft Office, won't be ready until fall. Without being optimized, most programs written for older versions of the Mac operating system can run under OS X, but only in the so-called Classic environment, a built-in version of Mac OS 9.1. Also, the version of OS X that ships this weekend is unable to play DVD movies or burn CDs, although Apple CEO Steve Jobs promises fixes soon.
As a result, Apple is going with a soft launch for the product. The $129 software upgrade that goes on sale Saturday is being targeted mainly at so-called early adopters, the people who feel pretty knowledgeable about computers. In the summer, Apple plans to start including the OS X on its new machines.
The saving grace
So what is Jobs most proud of?
It's the new save panel, Jobs told reporters Wednesday when he unveiled the OS at Apple's headquarters in Cupertino, Calif. In OS X, a small, very simple save panel comes up, showing only the most likely places a person might want to save a document. However, with the click of a button, a complete file directory is available. In Windows and earlier versions of the Mac OS, the save panel has always been more complex and has a fixed, relatively large size.
Jobs said that making something simpler is actually quite difficult, as is making something more powerful. But with the save panel, he said Apple has done both.
"Doing something that is both at the same time easier and more powerful is really, really hard," Jobs said.
In another feature likely to be well-received, OS X is equipped to manage the amount of memory needed by each program automatically. In the past, Mac owners had to dole out memory to each program themselves.
"This is silly," Scott Forstall, director of application frameworks for Apple, said of the old method. "Users don't want to do that."
Many of OS X's features are aimed at laptops owners, with Apple executives noting that more and more computer buyers are opting for portables. On Wednesday, Tevanian demonstrated a Titanium PowerBook G4 waking from sleep mode as fast as he could open the case.
"This is instant on," he said. "It really works. When you can do this instead of (even waiting) 5 to 10 seconds...it gives you a new way to work."
A looker, too
Apple's improved graphics range from new key technologies to the kinds of obscure bells and whistles for which Apple is known.
Aside from just sporting a new look, OS X improves the way graphics are manipulated, whether it is a picture, a 3D image or a movie. The new operating system is also adept at managing the images as they move across a screen. For example, Apple executives showed how a thumbnail of a QuickTime movie can be dragged across an animated 3D image with both items partly visible, thanks to a powerful compositing algorithm.
Apple's graphics prowess is also evident with the screen saver, which offers a slide show of stored photographs. It zooms in and moves artfully from one photo to another. Such a move appears simple but is actually quite taxing on hardware.
In trying to plan for the future, Apple tried to use standard formats for many of the types of files that build up in a computer system. Preference files, for example, are stored in the Web format XML (Extensible Markup Language). Similarly, Mac OS X can output from any program as a PDF file, the type used by Adobe's Acrobat.
Deal said using file formats that are not specific to the Mac makes sense.
"Apple has certainly tailored OS X to the Internet environment," Deal said. "PDF is one of the most popular file formats for viewing text over the Internet."