A somewhat cool, non-free OperatingSystem from Be, Inc. (http://www.beincorporated.com/). Was particularly good with handling audio and video (though it lacked support for certain popular codecs, particularly QuickTime). It was pervasively multi-threaded, with multiprocessor support up to 16 processors (others were theoretically possible; the system was limited to 16 because they hadn't tested it beyond that), and used a TaggedDatabaseFileSystem that was ahead of its time.
Be's API was a pleasure to use- it's amazing what can be done when you start from scratch.
Unfortunately, Be, Inc. was dissolved in November of 2001. It is still (!) involved in a court case with MicroSoft, insisting that MS materially hurt BeOS's chances for success, thanks to MS's allegedly anti-competitive OEM practices. There is a spectacular example in Be's history of why they make this claim.
You used to be able to get it for free if you promised not to make money with it, at http://free.be.com/ but that site is now down.
See also: http://www.befaqs.com/news/readstory.php?story=56 (FAQ) for an explanation of why Palm was interested in Be.
Furtherless, the rumor in 2010 is that Palm is also not long for this world...
Actually, as of September 2003, Be have settled their suit with Microsoft (http://www.theregister.co.uk/content/4/32737.html). IMHO this is a tragedy. A large part of Be's demise was due to Microsoft's anti-competitive marketing practises, and to sell out for a few pieces of silver rather than to have it come out in court is a huge waste. I bought a copy of Be, and wish it still lived. Imagine an OS slightly cooler than MacOS X, that you could run on cheap hardware... -- RobertAtkins
Initially, Be developed BeOS. Later, it developed BeIA, which was based on BeOs, but was targeted at embedded devices. It then laid off a number of employees and focused the rest on BeIA. Then, in late 2001, PalmSource bought the assets and hired key staff (meaning BeIA engineers since that is all that was left, marketing and support staff having been laid off some time ago). BeOs may or may not have reached its EndOfLife.
Be was moving forward quickly in media fields, and then they announced their Internet Appliance strategy that had many software houses worried that they would be abandoned if they continued developing for Be. Officially, Be's position was that BeOS was not being abandoned; simply that the company was forced to concentrate its resources on something that actually had a competitive chance.
I just set up a new computer to run Windows and BeOS. My only other non-linux machine is a 486. Anyway, once I get BeOS installed (it was, but I had to reinstall Windows due to a driver conflict before I actually used Be on it), it will probably spend most of it's time in BeOS. Maybe. Due to poor graphics card, the machine isn't any good for playing 3D games, so the only real reason for me to run Windows on the machine is to play DVDs. Otherwise, it should be all BeOS.
Seems to be Unix under the hood. Try opening a terminal window. It has a bash shell and Unix directory structure. Does anyone know more about this?
It's PosixStandard compliant, so it has a notion of users and groups and all sorts of other unix stuff, but it isn't unix.
Actually, a very cool OS. And while it tries to look a bit like Unix in terms of directory structure and use of the bash shell, it's based on a completely different kernel and windowing system.
It's written in C++, completely multithreaded from the ground up, "optimized for media applications" (whatever that means - to me, it means it does video very well), and handles huge files with ease. [BeOS is capable of handling 64 bits at a time, which makes it much better at handling multimedia applications]
Don't forget the open source reimplementation of the whole OS for the x86 platform: http://www.openbeos.org/
It's a humongous project, but they seem to be making real progress!
Sony picked Be for a new internet appliance, as reported at http://news.cnet.com/news/0-1006-200-4401294.html
HaikuOs?, found at http://www.haiku-os.org/ , is currently (2011) the BeOs clone making the most progress, and is OpenSource to boot. It may feel a bit dated (the GraphicalUserInterface is much like the original BeOs, for example) but it is reliable and you can get from BootLoader? to desktop in under a second with a fast disk. A LiveCd can be downloaded form the site, and it runs well in qemu and on actual hardware.