Such outreach is particularly important for RIM because it is using a new, proprietary operating system for the PlayBook and thus cannot assume that existing BlackBerry developers will write applications for it.

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Like its predecessors, the newest PalmPilot, the Palm III, is one of the best-designed bits of consumer electronics ever made. 3Com's proprietary operating system, the Palm OS, is amazingly intuitive and perfectly adapted to a device that most users turn on for mere seconds at a time.

FORBES: Small and beautiful

There is no doubt that HP is getting a large patent portfolio, a strong team of engineers, and a proprietary operating system in Palm webOS, and it is reasonable to assume that HP did not have other ways to acquire such assets for less than the price it is paying for Palm.

FORBES: HP's Palm Purchase: Pennywise But Pound Foolish

Nokia has been making smartphones for years, using a proprietary (and aging) operating system known as Symbian, that is almost unknown in the U.S. but that is in heavy use all around the rest of the glob e.

FORBES: Don't Count Nokia Out Yet

Microsoft is hated chiefly because it represents the opposite model, proprietary software, and because its operating system, Windows, is the main rival to Linux, the best-known open-source software today.

ECONOMIST: Computer security

Apple's operating system, meanwhile, is proprietary and viewed as more secure.

WSJ: Pentagon Expects to Enlist Apple, Samsung Devices

Actually, Dreamcast will ship with two operating systems, a proprietary one from Sega and Windows CE, Microsoft's "lite" operating system for consumer devices.

FORBES: Pixelated dreams

In the past, Sun sold only proprietary boxes that included its own chips and Solaris, its own operating-system software.

ECONOMIST: Sun Microsystems

As a group, the aristocrats suffer from subpar operating momentum and rich valuations, averaging quadrix momentum scores (my proprietary rating system) of 47 and value scores of 49.

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